Rossignol .pdf



Nom original: Rossignol.pdf
Titre: [halshs-00137198, v1] Figures de l'historien dans le cycle de Dune de Frank Herbert
Auteur: Rossignol, Benoît

Ce document au format PDF 1.6 a été généré par HAL - CCSd / PDFlib+PDI 7.0.2 (PHP5/Linux), et a été envoyé sur fichier-pdf.fr le 10/11/2011 à 13:46, depuis l'adresse IP 41.141.x.x. La présente page de téléchargement du fichier a été vue 1547 fois.
Taille du document: 242 Ko (17 pages).
Confidentialité: fichier public




Télécharger le fichier (PDF)










Aperçu du document





!#" !$ % &' % ( )' *

Manuscrit auteur, publié dans "N/P"

+

, - .0/212354762398;:=<7- 4?>A@012-$3ABC6;DEBF478G3IHKJFH;8A39623MLONQPERS6T3U,WVX<Y3A1TZ[3A1E>
\^] _a`cbed f^` g$g h iX_X`Xj

halshs-00137198, version 1 - 17 Mar 2007

k l#m%_on +X+%prqcsMtvu iX_X] q E
[
] kw] d `ox x yQ_X]
+
… ‡?Š%| ] tAq ]2j~] s{t gw€ t `‹€ t ]cg'Œ Xs Xt ]‚g €{` s{t
qcsOŠ Œ s{tAq ]Tj=l~h _‚d t h i s ] qcsO‘cs m d t h u Ž ]E`X€

s{z'| #h g}d ` t ~h ] _g q h#g €{m ts{t ] _‚d q m _{gTgvmYƒ'h d m q ] j j~]„y†… t}‡ j~ˆcg2g s{t j‰]
m  `Xh t'Ž ] c_ d}h ] z=z=t `‹_‚d ˆ Ž ] _‚dXx j†g l#m%iXh d q l s _ z m h dQ…ah~] _7ˆ j~`Xh iX_aˆ
s g qcsOŠ ’XŠ j~] q ]5“ s _X]„y•”—– ˜A™QšA›%œ ›„•œ ž#ŸY ¡›„Y¢{›AŸY•£{›‚y ‘cs h†gv]

g h¤d s ] + ¥{¦X¦ m _g§€Xj s ;
g d m t q  ƒA] €{]%_ q m _‚d;j~]¨j~] Š d ] s{t m d=d ]%_cd}h z _X]¨€{] s d Ž m%_ ‘cs ] t§q ]©g l ’ m t t ª d ] t y«€{` s{t
q ] sX¬­t m h#gv`‹_{gFm sUŽ `X h _{g Q“¨l s _X]—€{m t d y'j~m Ž ]%_cd}h~`X_M€ t ˆ Š h#g ] q ] Š ] z m h¤dFg ]Yd t ` sX ] q m%_g s _ t m €X€{` t d
€ t ˆcgv] _cd ˆ Š ` Ž§Ž ] s _X]2€Xh u„Š ] q l¡m t Š%| h  ]„y s _X]0gv` s{t Š ] | h#gd ` t h ‘cs ] ‘cs h ]%_ Š h d ] s _a]Tm s d t ]„y s _ Ž m _ s g Š t h d
t ] _  ` ’ m _cd7j s h~® ŽFª Ž ]°¯ s _±d ˆ Ž `‹h iX_am i{]M` t m j²'³ t Š | h  ]„yGd ˆ Ž `‹h _{g y Š t h d}h ‘cs ] n
g ` s{t Š ]‚g[´ Š l#]‚gdWm s g ]%h _ q l s _ q h#g €{` g h d}h z j h d=d ˆ t m h t ] Ž h Ž m _‚d j~]Kd t m  m h j q ]5j=l | h¡gd `
t ˆ Š h d q ]¶g `X_·m%_Xˆ„m _‚d}h#g$gv] Ž ] _‚dK“¨l¡m s d t ]°€{m t d Š ]±€{] d}h d z m h¤d—]cg}d—ˆ  ` ‘cs ˆ°€{m
t ] € t h#g ]cgG´ q m _g¸j~] q h~m j~`Xi s ]°] _‚d t ]º¹T»§hA¼7` t ] ]°] dFj=l~h _ ‘cs h¡g h d ] s{t
q ]cg €{`ad}h#g Ž ] t | ˆ d ` t h ‘cs ]—] _‚d t ]¸¾±`‹_a]„`°] d[kw] d `Mx x ¥ ] dEgvm _g q ` s d ]
] _‚d t ]C¿XŒ s{t ƒ | ] _X`{] | ] dYkw] d ` À{E¿Xh iX_ h z h Š m d}h  ] Ž ]%_cd Š ] q ] t _•h~] t

Š ` E
Ž Ž ] s X_ ]o€Xh u Š ] q
k[l¡m _X] Š q `ad ] =z t m €X€{] q
kw]cg t ˆ z ˆ t ] _ Š ]cg | h#g}d `

] d t ] Š ` s {€ ] Ž ]%_cd q ]cg
t h~] _ ‘cs ]Eg s{t Xi h dµj~]G… t ] z
t m h j j~] s{t gO¯±€Xj s g h~] s{t g

h ¬ ‰h ] _X½Xy q m _{gYj‰] q ~h m j‰`‹i s ]°g s{t j‰]
q m _{g s _X—
] m j j s g h~`‹_ cq s°q h‰m j~`Xi s ]
€{mcgg m i{]U]cgd¸j s h§m s g$g hT€ t ˆ‚g ] _‚d ˆ

p
l#m tvŠ | h  ]„yKm%_•_X`•d ˆ„]r] d Š ` ŽEŽ ] _‚d ˆ„]r] d Š `‹_{gd}h d s m _‚dEÁ §ÃXÄXÄ{ʼn£{Ä{Åe›©ÅeÄMÆ{ eÇ Åeĕœ¡È É 
l#m s d m _cd^€Xj s gFg hWj=l#`X_ Š `X_ g h qXu t ]¨€Xj s g2j~m t i{] Ž ] _cd^j=lʘA™ËšA› œ ›„•œ ž#Ÿ7 #›„r¢{›0Ÿ7•£{›X
t h ‘cs ]cg ’ m …‹`‹_ q ] _cd2¿ s{t d ` s dYj‰] t ˆ Š h d¸]cg}d¸] _ Š m q•t ˆ q ] q ] sX¬ d ] ¬ d ]cg q l ¹Fm q h

\^] _X`•d=d `{y | h#gd ` t ~h ]%_•_X]O] d2m tvŠ |
Ž h j j~]Tm%_gwm s¨Ž `‹ h _{gwm € t u gWj~] q
j h at ]„y ‘cs l#m s©Š ` s{t g q ]Yg `X_Yd t m
Χ_X]5d ] _{g h~`X_Ïgv] Š t ˆ ]Em j~` t
j~] s{t g Ž ] _gv`‹_ i{]cg yËm _cd ˆ t h~]

ˆ„`Xj~`Xi s ]„y Š |
ˆ t ` s j~] Ž ]%_cd

m t {i ˆ„] q ]¨j~m̀ s …aj h Š m d}h~`‹_ qcs¸Í ` s{t _Xm j q ]¸kw] d `Mx x y ‘cs m d t ]
q ];j=l~h _cd t h i s ]•ckw];j~] Š d ] s{t m €X€ t ] _ qFŠ ] €{]%_ q m _‚d y¯Kj~m z h _ qcs
 m h jË] j j~]T… s d m¸g s{t j~m Š ] _g s{t ] q ]cg[m s d ` t h d ˆcgw€{`‹j h d}h ‘cs ]cg ] d t ] j h iXh~] s g ]‚g 
gA]%_cd t ] q ] sX¬¨z h i s{t ]‚g q l | h#g}d ` t h‰] _g[´ Š ] j j‰] q ]cgW_X] s{z m _X`X_ ’ Ž ]‚g  h Š d}h Ž ]cg q ]
s{t g[m srq ˆ t ` s j~] Ž ] _cd qcs—t ` Ž m _¸] d Š ] j j‰] q l‰¹Ðm q h\^] _a`ad=d `{y  h Š d}h Ž ] q ]0gv`‹_

q ˆcg h tAq ]  ˆ t h d ˆE] dW€{` g}d ˆ t h~] s{t m sOq ˆ t ` s j~] Ž %] _cd qcs—t ` Ž m _?ÑW] _{g h~`X_ ‘cs h h _  h d ]2¯;€ t
q ]Ej=l | h#g}d ` t h‰] _ q m _gAj‰] Š ’XŠ j~]Fm z h _ q l¡ˆ j s?Š h q ] t †
y €{m t j=l¡ˆ d s?q ] q l s _ Š mcg'€ t ˆ Š #h g y s a_ ]T€{m
Š ` Ž €Xj~] ¬ ]cg ‘cs hX€{] sX ] _cdµ] ¬ h#gd ] t ] _cd t ] | h#gd `Xh t ];] d«g Š h~] _ Š ]„® z h Š d}h~`X_ 

Ò#Ó Ô}ÕWÖ ×„Ø Ù Ú†Û~܁ݐÞ#ß à á¤Üâ á ã ä åcÝ áæÝ ç¤á ã è ޡ܁×$é á ê ë ì å•ìä¸í áæä î$ì{â ìïâ ìvð²Ø
ñ òó¤ä$â ìÞ~ä Ü ç ì à á¤î$ìä ôì?ã í%â é ìé ܁ä î õ Þ¡áæâ â ìäµÜ ôô}ã ë$äâö[÷ Ö$Ó Ô}ÕWÖ ×„Ø Ù Ú Ø
ø Ó Ô}ÕWÖ ×„Ø ù ú„Ø
û Ó Ô}ÕWÖ ×„Ø%ü=ý$ú Ø
þò å#ã ÿµì ã í ã ë$Þ‚Ý ç¤ã ã î ìï ì ô=ë$â á ã ä%å#÷vÖ$Ó ÔÕWÖ × Ø%ü Ú ú„Ø

ˆ Š #h gv] t j~]cg z h i s{t ]cg
t d}h~] q ]cg t m%€X{€ ` t d g

( Q
}
‚
¼Y`•d t E
] ˆ d s?q ]E]cgdWj h Ž h d ˆ„]2m s̊ ’aŠ j~] q ]^“ s _X]2] _cd ]%_ qcs—q m%_g s _¨g ] _{g t ]cgd t
j~]cgAg h ¬7t ` Ž m _g q ]
t m _ E¹Ð] t …‹] t d„f;]‚gd t h Š d}h~`‹_ ‘cs hX_ l¡mK€{mcg'g ] s j~] Ž ] _‚d s _T…
g s{t d ` s d ¯ s _a] t ] Š | ] tvŠ | ] q ] Š ` | ˆ t ] _ Š ]•ckw] Š ’aŠ j~]Eg ] q `‹_ _X]2¯5j h t ]„y z h _Xm j~] Ž
q l s _ #z s d s{t
Š ` Ž €•d ] q ]
Š | m ‘cs ] t `

d t u W
g j~`Xh _‚d m h _ ‚k[l#m qXq
Š ] c‘ s Ë
h m  m h d ˆ d ˆE€ t
Ž m _ ]cg}d¨j=l¡` Š Š mcg h‰`‹_

h¤d}h~`‹_¨g s?Š„Š c] gg h 
ˆ Š ˆ q ] ŽEŽ ] ‚_ dAˆ
q ] t ] Š `X_g h q ˆ

n
]%h _cd y_a] Š `‹_{g h q ˆ t m _cd ‘cs ]
s dˀ t m d}h ‘cs ] Ž m h#g t ˆ €{`‹_ q
] _cd y Š ` ŽEŽ ] s _a] | h#g}d `‹h t ]

] q ] Š | m c‘ s ] t ` Ž m _7mKd ` s%Í ` s{t g qc‡
Š t h d y g s{t j~]E€ t h _ Š h €{] q ]E_X`X_X® Š `X_cd t m
t ] t d ` s d¨j~] Š ’aŠ j~] q l s _ `{] h j2_X` sX

g ] z m h t ];] _2d ] _Xm _‚d
q h Š d}h~`X_Xy ŽFª Ž ]Yg h

]„m s ;ƒ;l#]cg}d Š ] d=d ]
s?q•t h~`X_g;h _cd ] t t `‹i{] t ¯0d t m  ] t g;j~mY€Xj~m Š ] c‘ s ]Yj~]cg | h#gd ` t h~] _{g ’
h#g}d `‹h t ]M] d¨gv`‹_Iˆ Š t h d s{t ]±gv]±gv`‹_‚d7ˆ j~m …‹` t ˆ„]cg q m _g Š ]©d t m  m h j

t ] %Š | ] t Š%| ] q ] Š ` | ˆ t ] _ Š ] ‘cs ]Y_X` s g  `
` Š„Š s €{] _‚dA´ ‘cs ] j j~]cg t ˆ z j‰] ¬ h~`X_g—g s{t j=l |
q l¡ˆ Š t h d s{t ] Š `X_cd t m%h _cd ]7] dAj=l s _•h  ] t g ‘cs h«g l ’Oq ˆ €Xj‰`‹h~] Fƒ;l¡]cgd[¯ Š m s g ] q ] Š ] d=d ] Š `X_cd t m h _cd ]F®Aˆ j~m …‹` t ] t
s _X] t ˆ z j~] ¬ h~`X_ q m%_g^] d'€{m t s _ s _ h  ] t g Š ` | ˆ t ]%_cd ® ‘cs ]E_a` s gA_?leh _‚d ] t t `Xi{] t `X_gA€{m‚gAj~]cg[m s d t ]‚g'd ] ¬ d ]cg
q ]0¹Ð] t …{] t d y«] d Š l#]cg}d[€{m t Š ] ‘cs ]Y_a` s g  ` s j‰`‹_{g t m €X€{` t d ] t2Š ] d=d ] Š ` | ˆ t ] _ Š ]¨¯ s _rm s d ] s{t;‘cs ]0_a` s g
halshs-00137198, version 1 - 17 Mar 2007

] ‹¬ Š j s `X_g q ]K_a`ad t ];ˆ d s?q ]Kj~]cgWm Xq q ¤h d}h~`‹_{g t ˆ Š ] _cd ]cg m s¸Š ’aŠ j~]•
! " # $ % &(') * +% &-,. / V

kw] Š ’aŠ j~]Im t d}h Š s ‰j ]±d t `Xh#go€{ˆ t h~` q ‚] gυXh‰] _ q h#g}d}h _ Š d ]cg Kkwm9€ t ] Ž h u t ] yÐj‰m±€Xj s gOm _ Š h~] _ _X]°€{` s{t j~]cg
€ t `•d m i{`X_•h#g}d ]cg y7] d ‘cs hFj~] s{t ]‚gdOj~m X€ j s g Ž m j Š `X_•_ s ]„yY]cg}d Š `‹_{gd}h d s ˆ„] q ]9_X`•d t ] | h#gd `Xh t ]„y q ]9j‰m
s 020§u Ž ]Fg h u„Š j~]F´X]cg €{m Š ] q l | h#g}d ` t h Š h d ˆ Š ` ŽEŽTs _7m s j‰] Š d ] s{t ] dWm sX¬ €{] t g `X_•_am i{]cg q ]5j‰m
€ t ˆ | h#gd `Xh t ]§m 1

z h Š }d h‰`‹_?•x j{_ l¡]cgdµ€{m t d m i{ˆ;€{` {s t d m _cd ‘cs ]^d t u g«h Ž €{m t z m h¤d ] Ž ] _‚dckwm q ] sX¬ h u Ž ]5€{ˆ t h~` q ] Š ` sXat ]Kj=l¡]cg €{m Š ]
s q ˆ … s d q ]Ïj~m—_Xm t t m d}h~`X_ qcsIŠ ’aŠ j~] «ƒ;l¡]cgd2j‰mπ{ˆ t h~` q ] Š | m t _ h u t ]„y ‘cs h
d ] Ž €{` t ] j ‘cs h'_X` s gYvg ˆ €{m t ] qcI
ˆ d m …aj h d^j~m z h Š d}h~`X_ †kw]Y…{`X_ q €{m t ® q ] j‰¯Ì_a`ad t ] z#s d s{t§‘cs leh j z m s d5m Š„Š ] €•d ] t €{` s{t m q•| ˆ t ] t m s­t ˆ Š h¤d kw]cg
t ` Ž m _{g'_X` s g z `X_cd q ˆ Š ` sXat h t ] d Š `‹_ _Xm$b~d t ]Tj~m5d t `‹h#g h u Ž ]2€{ˆ t h~` q ]„y ‘cs h Š ` ŽEŽ ] _ Š ] q m _{g«j‰m Š h _ ‘cs m _‚d ]
g ]%€•d}h u Ž ]—m _•_aˆ„] q ]Ìj=l43 Ž {€ ] t ] s{t ¿ | m qXq m Ž x65 ®2m _ +%¦Q+ 7Q+¨q ]¨j~m98 s h j q ]• ¾Um%j i t ˆ Š ] d=d ]Y€ t ˆ Š h#g h~`‹_
m €X€{m t ] _cd ]°_X` s g—_X] g m s{t ‰h `‹_{go] ¬ m Š d ] Ž ] _cd¸j~m g h d s ] tOq m _{gÏj‰] z#s d s{t y q `X_cd—g ] s j;j‰] Š m t m Š d u t ]ºd t u g
j~`Xh _cd m%h _7]cgd mcg$g s{t ˆ•;:µm t j~mEg s h d ]2] j j~]Eg l¡ˆ d ] _ q g s{t s _F€{] s €Xj s g q ] +%¦X¦X¦X¦ m _{g < „“F] Š ] d=d ]Gd t u g j‰`‹_ i s ]

qcs{t „ˆ ]Cj‰]Cj~] Š d ] s{t _?l#m ‘cs l s _a]  h#g h~`X_ z=t m i Ž ] _‚d m h t ] y0… t h#gvˆ„]¶€{m t°q ] sX¬ j~`X_•i s ]cg­] j j h € g ]cg Tk[l s _a]
Š ` sXXt m%_cd;j‰] t u Xi _X] q ]¸kw] d `Mx xE®
¦(= m _{g§® y«j=l¡m s d t ] Š ` sXXt m _‚dEgvm _g q ` s d ]̀Xj s g q ]Ïg h ¬rŽ h j j~]¨m _g
½ À
g ˆ%€{m t m _‚dWj~m z h _ qcs—t u iX_X] q ]Kkw] d `Yx xw] d j~] q ˆ … s d q ]cg >@? œA?‚Å~  BXX› ÇA¢{›AŸY•£{›ac“F]‚g«h _ q h Š ]‚g«€{] t Ž ] d=d ] _‚d

m s j~] Š d ] s{tAq 0
] g h d s ] tAq m%_g Š ]cgA] j j h € g ]‚g q h z=z ˆ t ] _cd g ˆ  ˆ _a] Ž ] _‚d g y Š ` ŽEŽ ]5j~]K… ‡?Š%| ] twq ]cg |
j~]cg z ` s h j j~]cg q l ¹Fm q hF\^] _X`•d=d `†Tkwm q ] sX¬ h u Ž ] €{ˆ t h~` q ]S]cg}drm s g$g h s _a]  mcgd ]S] j j h € g ]
‘cs ] j ‘cs ]‚g'h _ z ` t Ž m d}h~`X_g z#s iXh¤d}h  ]cg  3'j j‰]0g ] q h  h#gv]E] _ q ] sX¬ y m s d ` s{tAq l s _¸ˆ  ˆ%_X] Ž ]%_cd z `X_

h#g}d ` t ~h ] _gw` s
€{] s €Xj‰ˆ„] q ]
q m d ] s{t €{` s{t

t Š ] _cd q h ¬ g h u Š j~]cg q l¡] ¬ €{m _{g h~`X_¨g €{m d}h‰m j~] = y j‰]DCh | m qFz#s d
d ` s dWj~] Š ’aŠ j~] y j‰]2C$h | m q \ s d}j~ˆ t h‰] _  : t ˆ Š ˆ q ˆT€{m w
E Ó Ô}ÕWÖ ×„Ø%ü Ú Ù%Ø
F ò6‚
G ìäËâ é ã ë%å#܁ä î ì Ü}Þ=åXå#áæä ô}ì(H‚ì}â ã ó¤ó Ý ì è ܁äQé á åcÿµìâ Ü}ÿ ã Þ~×$é ãå#á å#÷ ÖJI Ô}ÕWÖ ×„Ø KÚ
L ÕNM OA P Ö$܁×$× ìä îá ô}ìó¤ó~Ö × Ø Q Ù ú„Ø




!#" !$ % &' % ( )' *
½

q h t h i{ˆ
€{] s d ª

Š X` _cd t ]Tj‰m Š t ˆ„m d}h~`‹_¸] dWj=l s g m i{] q ]cg Ž m Š | h _a]cg'€{]%_g m%_cd ]cg ‹x j h _Xm s i s{t m s _a] u%t ]T` ¨j²l | ` ŽEŽ ]5_a]
d t ] t ] Ž €Xj~m Š ˆ•Xƒ;l¡]cgd qcs C$h | m q7‘cs l#ˆ Ž ] t {i ];j=l#` t q•t ];m s gv] h _ qcs?‘cs ]%j g ]Tg h¤d s ]Kj~] q ˆ … s d qcs¸Š ’aŠ j~]F´
h jËm  m j‰] s{tAq ]5d t m s{Ž m d}h#g Ž ]Th _am s i s{t m j~y q l¡ˆ  ˆ%_X] Ž ]%_cd z `X_ q m d ] s{t q ]5d ` s d ]2j~m z h Š d}h‰`‹_?a“Ð] sX¬ÌŠ `‹_{gd m d g
g l~h Ž €{` g ]%_cd kw]Y€ t ] Ž h~] t €{` s{t^Š `‹_{gd m d ] t j~] q ˆ Š m j~m%i{] Š | `‹h#g hQ€{m t ¹F] t …{] t dA€{m tKt m €X€{` t d[¯ s _a] t u iXj‰]

| m …Xh d s ] j j~] q 9
] j~m¶g Š h~] _ Š ]„® z h Š }d h~`‹_ j~m9€Xj s g Š ` s{t m _cd ]Uj~`
t ˆ i t ]cg$g h~`‹_ d ] Š | a_ `‹j‰`‹iXh ‘cs ] y ~j ] z#s d s{t _a] g l~h _{g Š t h¤d
d ] Š | _X`Xj~`XiXh ‘cs ]Ï] dEg Š h~] _cd}h z h ‘cs ] Š ‹` _‚d}h _ s  ³ s­Š `‹_‚d t m h t ]„y
g Š h~] _ Š ]„® z h Š d}h‰`‹_7] dWg s{tWŠ ] ‘cs h~y‹€{` s{tQs _Ej~] Š d ] s{t yXh q ] _‚d}h z h~]

t g c‘ s ~l h jFˆ Š t
€{mcg q m _g

q Š%t ˆ„] s _a]
h  h dFŸ7•£{›XKkw] Ch | m ·
s _X] €{] t g €{] Š d}h  ] q ] € t `Xi t u g
h j ’ mYj~¯ s _ Í ] s g s{t j~]‚g Š `X_  ]%_cd}h~`X_g q ]Yj‰m
s _X];ˆ%€{` ‘cs ] q `X_•_aˆ„]• ƒ5l¡]cg}d m s g$g hXj‰] Ž ` ’ ] _

halshs-00137198, version 1 - 17 Mar 2007

q l¡] ¬ X€ j h ‘cs ] t _X` Ž … t ] q l#ˆ j‰ˆ Ž ] _‚d gYg €{ˆ Š h z h ‘cs ]cgЯÏj=l s _•h  ] t g q ]0ŸY•£{› y
m d Ž ` g € |au t ]og hW€{m t d}h Š s j h u t ]¨] d Í}s gd}h z h~]%_cd2g ]cg5mcg €{] Š d g Ž ˆ q h~ˆ  m sX¬ ` s
h _  h d ] t ¯ s _¨m t t ª dAg s{t j~]T_X` Ž qcs Ch | m q y ‘cs h _a]T€{] s dwm  `‹h t ˆ d ˆ Š | `‹h#g h
tˆ zˆ
tˆ zˆ

‘cs h Š `‹_‚d t h … s ] _cd§¯ %Š t „ˆ ] t vg `‹_
t ] _am h#g$gvm _cd g  kw]Ïgv] Š `X_ q €{` {s t
z ` t d s h d ] Ž ] _cd ´•h j g l¡m iXh d q l s _a]

t ] _ Š ] Š ~j m h t ] ¯9j=l s d `X€Xh~]¶g m d}h t h ‘cs ] q ] ¿m ŽTs ] j;\ s d}j‰] t yG˜Aœ › 'Æ{ĕ£Ë
: t ] _ q•t ]Um s gvˆ t h~] sX¬ Š ] d=d ]
t ] _ Š ]„y Š ¡l ]cgdÌ`a…?g ] t} ] tO‘cs ]±j‰m±i{] _ u g ] q ]M“ s _a]±_?l#]cg}d¨€{mcg¨d m _‚d—¯ Š | ] t Š | ] t—q m _g s _ m  m _‚d
| h¡gd ` t h ‘cs ] ‘cs ] q m%_g s _¸m h j j‰] s{t g'j h d=d ˆ t m h t ]• 3'_‚d t ]Tj=l | h¡gd `Xh t ] t ˆ ] j j~]E] dWj~m q h~ˆ i u g ]„yQg l¡` sXXt ]E] d'g ]Kd}h~] _‚d

j=l¡]cg €{m Š ] q ]9j=l s d `X€Xh~] ] d q ]¶gv]cg  m t h~m%_cd ]cg©® qc’ gd `X€Xh~]cg y  ` ’ m%i{]cgO] ¬ d t m ` t q h _Xm h t ]cgO] dogvm d}h t h ‘cs ]‚g 
7
x _  h d m d}h‰`‹_F¯K€ t m d}h ‘cs ] tQs _a]Kj~] Š d s{t ] qc’ }g d `‹€Xh ‘cs ];] d«gvm d}h t h ‘cs ] qcs¨Š ’XŠ j~]

ƒA` ŽEŽ ]Ïj~]¨_X` Ž qcs C$h | m q j~] t m €X€{]%j j~]„y†Ÿ7•£{›Om …{`X_ q ]—] _ t ˆ z ˆ t ] _ Š ]‚g | #h gd ` t h ‘cs ]‚gE] d;j h d=d ˆ t m h t ]‚g y
€Xj s g7` s Ž `‹h _{gFh Ž €Xj h Š h d ]cg  kw]cg t ˆ z ˆ t ] _ Š ]cgF] ¬ €Xj h Š h d ]cg Š `‹_{gd}h d s ] _‚d y q m _g§j~m q h~ˆ i u g ]„y s _9gv` sX ] _•h t

Š `X_g Š h~] _‚d q 0
] j~mF€ t ] Ž h u t ]E€{ˆ t h~` q ]„y _X`•d t ] | h#g}d `‹h t ] t ˆ„] j j~] -3wj j~]cg;gv`‹_‚dA] _Yd | ˆ„` t h~] t m t ]‚g ‹kwm q h#g}d m _ Š ]
d ] Ž €{` t ] j j~] ‚] gd·h ŽEŽ ] _{g ]„y9j‰] Ch | m q m q ˆ d ts h d q ] _X` Ž … t ] sX¬ q ` Š s{Ž ] _cd gvy ] z=z m Š ˆ …ah~] _ q ]cg
+%¦
g ` sX ]%_•h t g  ƒA] €{] _ q m%_cd Š ]‚g t ˆ z ˆ t ] _ Š ]cg^] ¬ €Xj h Š h d ]cg[€ t ] _ _X] _‚d s _X]F€{m t d Š t `‹h#gg m _‚d ]Ym s©z h j qcs Š ’XŠ j~]•
q l¡m …{` t q € t ]cg ‘cs ]Ðh _X] ¬ h#gd m _‚d ]cg[´ Š l¡]cg}d'h _ Š h q ] Ž§Ž ] _cd ‘cs ] C ]cgg h Š m Š h d ]Y¿{m h _cdW³ s i s gd}h _ +X+ 
3wj j~]cg;gv`‹_‚d
kw] › Ç$Ç  #›C¢{› Ÿ7•£{› t cm gg ] Ž …aj~]C€Xj s
d t m _{g z ` t Ž ]Yg `X_¨€{m _aˆ i ’ t h#g d ]F] _—m t Š | h 
€{] t gv`‹_ _Xm i{] q ] kw] d ` x x U
® ] d gv]cg Š
g h iX_•h z h Š m d}h  ] Ž ] _cd €Xj s g i t m%_ q q ] t

+
g h~] {s t U
g m%j j s g h‰`‹_{gU¯CÁ j²l i{] q l¡` tUq ]Cj~m·Ñ«] t t ] É n y
h#g}d ]Ѐ{` s{t € t cˆ gv] _cd ] t ¯¨¿•d}h j i{m t 82] _•iXh¡g
| m _—] d ¹§h d}j~]
m €{m Š h d ˆcg q ] Ž ˆ Ž `Xh t ]·i{ˆ _Xˆ d}h ‘cs ] ®U] _cd t m$b#_X] s _

ˆ zˆ
”—– ˜A™QšA› œ ›„•œ ž¡ŸY ¡›„Y¢{›KŸ7•£{›X•kw]cg q ] sX¬Ìq

:µm

s j ’

t + ½ • kw]
_X` Ž … t ]

t ] _ Š ]cg | h#gd ` t h ‘cs ]cg q m _g ”W› Ç ˜A£}ÕÂX£?Å‰Ç {¢ › ŸY•£{› ] d
] t _ h~] t gwj h Xt ]cg'€ t `Xj~`X_•i{] _‚dw] dWh _‚d ] _g h z h~] _‚d Š ] d= d ]Kd ] _ q m _ Š F
] ´

çæë%å#á¤ìë$Þ²å‹ëâ ã × á¤ì å å µß ô ¡Þ ã ë ç¤ìäâXå#ã ë åç ì × ã á¤î åîìQç¤ìë$Þ²åô}ã ä$â¤Þ#Ü î$á¤ô â á ã ä åìâ‚îì†ç¤ìëÞXáæÿQÿ ã Ý á ç¤á åeÿµì ç¤ÜQå#ã ô}á ß}â ß í Þ¡ìÿµìä%Ö ç ¤ìÿË× áæÞ¡ì
î$ì H‚ìâ ãQó ó¡Ø H‚ìËç á¤ìäwìä$â¤Þ¡ìQç¤ì =áæé Ü î Xë$â ç¤ßÞ¡á ìäwìâ ç Êëâ ã × á ìËì åeâ ìï$× ç á¤ôáæâ ìÿ ìäâ Ü í í áæÞ~ÿ ßQîÜä%å I Õoã wç Ü G Þ å ã ä ã Þ¡ß ì ;Ü}â Þ¡á¤ÜÞ¡ô é ì
ô}ãvä í ì å=å#ì ò å#ô}á¤ìä ô}ìQé ã ç¤î åâ é ì ì å?â ã ë$â ãv× á Ü ÷ Û‰× Ø%ü ! ú%ð#ØAH‚ÜQà ì áæä ìµå#܁â áæÞ¡á ê ë ì#•" ìâ ô}ãvÿµá ê ë ì#•" ì åeâ ìï× ç¤á ô}áÊâ ìQîÜä%å{ç ¤Ü×× ìä î$á¤ôì ý'îì

ÕNM OAP Ø
Ò $ ò}â é ì× áæâ â ܁ä ôì ã í„îÜâ Üõ é á¤ô=éQâ¤é ì% Xëâ ç¤ìÞ¡á Ü}ä%å•ç¤ì í â%ë%å#÷ ÖÕ &§Ö ׄØ('vý Ø
Ò Ò Õ M#OAP Ö ×„Ø )ù '$Ö$ç¤ã Þ=å•îì ç¤ÜÞ¡ìä ô}ã ä$â¤Þ#ì?Ü à ì *ô ^Ü× ìvå•+ã µç ì{â )é ÿ ì î ëQ× Ü å=å#ß Ö$î$ì?ç Üâ¤Þ¡Ü ô}ì Ö$î$ì ç¤Üÿµßÿ ã áæÞ#ì?ì åeâ â¤Þ åc×$Þ¡ß å#ì}ä$â¡Ø
Ò#ñ•*Õ &±×„Ø ú
ý ,אÞ#ã × ã$å•î
ë - Ô O .0/ 1 2 × Ø%ü$ ü !#,×$Þ¡ã × ãå•î%ì 3 ܁ÿµÜ å•ì4â {Ü è î$Ü î%Ø
Ò#ø *Õ &EÖ ×„(Ø '% ü " 'Ú Ø

( Q
}
‚
j~]cgAd t m Š c] g q F
] j=l | h#g}d `‹h t ]Ðd ] t t c] gd t ]
s _¨d m …Xj~] m s q ] 5§m _ 8T`Xi | + À{( 3w_
́s h  ] ‘cs hX€ t ] _ q €Xj‰m Š ] q m _{g j=l s _•h 

¥

q ]  ‰h ] _•_a] _cd[m s $g g hˀ |c’ g h ‘cs c] g[´ q ]cgK€Xh u„Š ]cg[i t ] Š„‘cs ‚] g + ¥ ] d^g s{t d ` s d
z h _—m  ] Š j~]E€{] t g `X_•_Xm%i{] qcs ^
f m …•…ahË] dKgv`‹_¨i t ` s €{] Š ¡l ]cgdwj~m Š s j d s{t ]
+%p
] t g q ]G“ s _X] 

, / 1 % " % +% % %
¿Xhj=l¡ˆ €Xh#gv` q ] qcs … ‡?Š | ] t'q ]cg | h#gd ` t h~] _{W
g j~m h#gg ];€{] _gv] tW‘cs leh j{] ¬ h#g}d ] cq s{t m _‚dQj‰] t u iX_X]
Š ` ŽEŽTs _am s d ˆ q l | h#g}d ` t h‰] _gw€ t ` z ]‚g$g h‰`‹_ _X] j#g ® ¹Ðm q h‹\^] _a`ad=d `¨ˆ d m _cd m s g$ g h s _a] q ] Š ]cgW€
h j#gw_ l¡`‹_‚d Í m Ž m%h#g'j~] Ž `‹_a`‹€{`Xj~] q ]2j=l#ˆ Š t h d s{t ] q ]Tj=l | h#g}d `‹h t ]„y Š l#]‚gd ® ¯„® q h t ];j~m5_am t t m d}h~`‹_ t

halshs-00137198, version 1 - 17 Mar 2007

` t {i m _•h¡g ˆ„]2] dQd t m _g Ž h#g ] y q ]cg z m h d gw] dµh _cd t h i s c] gW€{mcg$gvˆcg XƒA] d=d ]
j h Ž h d ]cg h Ž €{` t d m _cd ]‚g[´ q l s _X] €{m t dSj‰] ŽT’ d | ] yMj~m j~ˆ%i{] _ q ]
€ t `X€{m i{m _ q ]„y Š ]cg q ] sX¬ j h Ž h d ]cg'€{` sX m%_cdW€{m t z `Xh#gvy Ž m h#g'€{m‚g«d `

q ˆ z h _ h d}h~`X_Ed t `
] d q l¡m s d t ]

q ]Gkw] d `0x x s _a]
t ` z ]cg$g h~`X_•_X]%j#gw®

] Š `‹_ _ s ] Xt m%h~]„y
sX „] y q m _{gWj~] Š ’XŠ j~]„y q ] sX¬
€{m t dSj~] Ž ] _gv`‹_ i{]„yºj‰m

s%Í ` {s t G
g gv] t ] Š ` s €{] t •x j z m s d m Í ` s d ] t'Š ]
‘cs h Š `X_g}d}h d s ]Y_X`X_o€{mcg s _a]0d t `Xh#g h u%Ž ]Yj h Ž h¤d ]„y Ž m h#g;j~m Š `‹_‚d t m q h Š d}h‰`‹_o_aˆ Š ]cgg m h t ]Ïg s{t j~m ‘cs ] j j~]  h~] _‚d
g l¡`X€X€{` gv] t d ` s d©] z=z ` t d | h#gd ` t h ‘cs ] y0j=l¡` s a… j h=;ÎE_ Š ] t d m h _·_a` Ž … t ] q ]9€{] t gv`‹_ _Xm i{]‚go€{] sX ] _cd ª d t ]
q h#g}d}h _•i s ˆcg q m _gwj~] Š ’aŠ j‰] Š ` ŽEŽ ] q ]cg | h#g}d ` t h~] _g •¾U] _‚d}h~`‹_ _X`X_g … t h u  ] Ž ] _cd q l#m …{` t q j~] s{t« t j~] q m _g

¬ d ]  ¶d t m  ] t gµj~] s{t gWˆ Š t h d gvy‹h j¡g Š `X_cd t h … s ] _cdµ¯ Š t ˆ„] tWq ]cgW] z=z ] d g q ] t ˆ„]%j#g y g h Ž2s j~m _cd s _
d q l#m …{` t q ]%—
_ ` t i{m%_•h#gvm _cdWj~m2€ t ` z `X_ q ] s{tAŠ |•t `‹_a`‹j~`XiXh ‘cs ] qcs—t ˆ Š h d y ] _ Š `‹_{gd ts h¡g m _‚d q
s
s{t d ` s d y ] _¨g h ŽTs j~m _‚d s _a]5h _‚d ] t d ] ¬ d s m j h d ˆ ‘cs h{h _g Š t h dµj~]Gd ] ¬ d ] qcs¸Š ’aŠ j‰] q m _g s
3w_g h¤d ]T] dwg
g s €X€{` g ˆ Š ` | ˆ t ] _‚d ] d†…ah~] _E€Xj s g  mcg}d ]„y{] _gv] Ž …Xj‰];ˆ  h q ] ŽEŽ ] _‚d z h Š d}h z yX_ l¡` z=z=t m%_cd q ]K€{] t g €{]
j~]Kd ]
ÑW` s

d t ` Ž €{]„®j²leŒ2h j Ž m h¡g2¯Yj=l¡] z=z h Š m Š h d ˆ t ] Ž m t ‘cs
Š ’aŠ j~] y ¯5j‰mÐg h ŽTs ~j m d}h‰`‹_ q ];j=leh _cd ] t d ] ¬ d s m j h¤d ˆ
g s{t d ` s d q l s _a]  mcgd ];€{m t m d ] ¬ d s m j h¤d ˆ„yj~]Gd ] ¬
] _‚d ` s{t ˆ q ]±d ] ¬ d ]‚gMg s …‹m j d ] t _X]cg[´ q c] go€
Š | m €Xh d t ]•A³;h _{g h~y;j~]cg—`{] sXat ]cg q ]cg | #h g}d `
Š `X_g}d ts h#g ]%_cd q m%_g2j~] s{t2t ˆ Š s{t t ] _ Š ]„y'` s

]cgA] j j h € g ]‚g 
_Ð] _gv] Ž …Xj‰]

Š d}h  ] c‘ s #l ] _
m …aj~]•kw]cg^`{] sXXt ]‚g q l | h#g}d ` t h~] _g2g ]F€ t ª d ] _‚d'…Xh‰] _Xy q m _{gKj‰]
+ s
<Ym
g ] _{g t ]cgd t ] h _cd cq s d ] t Ž ]T® h _{g ] t d}h‰`‹_ q ] Š h d m d}h~`‹_Ю ] d
d ] q ]G“ s _a]Tg ] q `X_•_am _cdµ¯  `Xh tWŠ ` ŽEŽ ] s _2d ] ¬ d ]K€ t h _ Š h €{m%j

t `‹j~`Xi s ]cg Ž m h#g g {s t d ` s d¨j~]‚goˆ%€Xh i t m € | ]cgO` sXat m _cd Š | m ‘cs ]
t h‰] _g—` t i{m _ h#g ]%_cd s _a±
] g ` t d ] q ]º€{`Xj ’ € | `X_•h~]r_Xm t t m d}h  ] y;] d
j~] s{t h _‚d ] t ]%_cd}h~`X_oh _am s i s{t m j~] y s _r] z=z ] d q ] t ˆ„] j'gvm h#g h¡g$g m%_cd y

€ s h#g c‘ s 5
] j=l¡`{] sXXt ] q l | h#g}d ` t h‰] _Fh _ Š m t _X]2®«]%_Ðd | ˆ„` t h~]2® s _a]Tm s d ` t h d ˆ2] d s
j h d=d ˆ t m h t ];_ l¡] _ q ]  h~] c_ d ‘cs ]5€Xj s g«h _cd ˆ t ]‚g$g m%_cd j‰` t g ‘cs ]5j²l#`X_ Š `X_g}d m d ] ‘cs
Š `X_g}d ts h d j‰] t ` Ž m _ t ]%j~m d}h  h#g ] _‚d z ` t d ] Ž ]%_cd Š ] d=d ];m s d ` t h d ˆ•‚³ sX¬ ] z=z ] d g
Ž Ž ] t ] z=z ] d q ] z m Ž h j h‰m
j=l¡`‹_¨€{` s{t t %m h d'_a` §
Š Š ] ‘cs h q ] Xt m h¤dWj s h ª
g ] z m Ž h j h‰m t #h gv]Em  ] E

| ` t g ® d ] ¬ d ]•

t h d ˆ• 8 t Š ]Fm sX¬Oq #h g Š `
d t ]§ˆ d t m _ i{] t •ÎE_ s •_ h 

_X];h _g}d m _ Š ] q ]  ˆ t h¤d ˆ• kw]
]Kj~]cg z h i s{t ]cg q l | #h g}d ` t h~] _g
q ] t ˆ„] j~yXh j z m s dµm Í ` s d ] tWŠ ]

Í]s
‘cs ]

‘cs ]
s{t g q ]cg | h#g}d ` t h~] _g qcsOt ˆ Š h d'j‰]Tj~] Š d ] s{t
] t g q ]0g Š h‰] _ Š ] ® z h Š }d h~`X_Xy?m s¨Ž `Xh _{g«j‰` t g

Ò#û ò}ó é Ü à ìâ õ ã†ì ܁ޡç {Þ#ì ì áæäWå#á¤ç à ìÞ ܁ä îQÜ× ìÞ¡í ì ô=â„è ã ç¤îQã Ý ã ç~Ø ÷ I ÕWÖ × Ø%ü6Q$Ú Ø
Ò=þ ò X(Ô . .0/
P / . XÔ(1 AP P Ø #ö O 6P O). / OWÓ Ô
! Ø G„é ì â¤é áæä èËî$܁â ì î í Þ¡ã ÿ—Ü â áæÿ ìËå#ãQÜ}ä ô}á ìäâ â¤é Ü}â„ã ä ç ޡ܁ޡìÞ¡ìÿËä ܁äâ~åXåeë ô éµÜ å
â¤é á åc× Ü áæä$â áÊä è Þ#ì}ÿ Ü áæä ì î â ãËå#ìä îQÜ×é å#á¤ô}Ü ç áæÿQאޡì å=å#á ã äµî$ã õ äQâ¤é ì?Ü è ì å#÷ ÖJI Ô}ÕWÖ ×„Ø%ü=ú ùQà ã áæޕÜ}ë%å=å#á4 I ÕWÖ ×„Ø%ü}Ù ú
Ò E ò}ó â á åcאޡãvÝ ÜÝ ç¤ìâ¤é ܁â ÜÞ¡ÜÝÝ á%í Þ¡ãvÿ¸Üä ô}á¤ìä$â%â áæÿ ìvåcõ ã ë ç¤î†ä ã â í áæä î†é áÊÿ å#ì ç¤í„ã ë$â ã í%× ç¤Ü ôì{Ý ìé áÊä î†â¤é
ì " ܁Ý$Ý Üâ¤éQÿ áæä ã Þ¡Ü ã í„ Ü =ì}õ á åeé
é ã ë å#ìé ã ç¤îQáæä ã ë$Þ Ü è ì ÷vÖ I ÕWÖ ×„Ø Ú Q Ø
Ò F$# í¡ Ø Q Ø ìä ìâ â ì &Ö % / ('*)* P . P ,+.- /$-/ . . 0 1 / . M 1 P /AM P& #Ô O1 2 AP3
1 0
Ö " ìë á ç Ö Ü}Þ#á å=ք ü ' Kvý Ö ×„Ø Ù "²ü ú„Ø




!#" !$ % &' % ( )' *
q ]Eg `X_Fm €X€{m t ¤h d}h~`‹_ay]‚gdˀ{m tWq
€Xj~m h¡g h t g qcs i{] _ t •] '³ sSz h j q
| ` t h `‹_ q l¡m d=d ] _‚d ]•-3w_Ïg Š h~] _

ˆ z h _ h d}h~`X_F] ¬ `ad}h ‘cs K
] €{` {s t g ]‚g j~] Š d ] s{t g y q ˆ t ` s d m _cd y Š l¡]cgd ŽFª%Ž ]Kj~¯ s _ q ]cg
Ž Ž ]r{€ ` s{t d ` s d t ` Ž m _XyKj~]rj~] Š d ] s{t g ] Š `X_gd t}s h d s _
]±gvmºj~] Š d s{t ]„y Š ` E
Š ]„® z h Š d}h~`‹_ay €{m tAq ˆ z h _ h d}h~`X_Yj~]2j~] Š d ] s{t h iX_X` t ]Tj~]‚g t u iXj‰]cgA] dWj‰]cgA] _ Í ] sX¬Ìq ]

j=l s _•h  ] t g ‘cs ]Ej=l¡m s d ] s{t m Š `X_gd t}s h d g y d ` s d m s €Xj s
` sSqcs g ` s g ®i{]%_ t ]o€{` s{t m _cd}h Š h €{] t A¿Xh q m _{gEj~]
Š ] t d m h _F_X` Ž … t ] q ] q `‹_ _Xˆ„]‚g yh j{_ l¡] _ t ]cg}d ]5€{m‚g Ž

halshs-00137198, version 1 - 17 Mar 2007

q ]Eg s{t € t ¡h g ]„yj‰` t g ‘cs ]5j²l | `
€{` s{to‘cs °
] j~]°j~] Š d ] s{t € s
q l¡m d=d ] _cd ]Eh _‚d ] _g h z h~ˆE]%_Ïg s

À

gA€{] s d ®h j g l#m €X€ sX’ ] t g s{t j~]‚g Š `X_  ] _cd}h~`X_g qcs i{] _ t ]
Š m q•t ] cq sIŠ ’XŠ j~]„y'j~]cg§j h Xt ]cgE€ t ˆ Š ˆ q ] _‚d gF` z=z=t ] _cd s _
`‹h _{g ‘cs l s _ q ]cgw] _ Í ] sX¬7qcs d ] ¬ d ];]cgdËj~]G…‹`‹_ q ` g m%i{]

t h ‚`‹_ q ¡l m d=d ] _‚d ] qcs ~j ] Š d ]
h#gg ]9g s h Xt ]Mj~]‚g—] _ Í ] Xs ¬
g €{] _gv]•X³;h _g h~y j~]cg | h#g}d `

s{t c] g}dQ€ t h#gW] _ q ˆ z m s d y Š ‹` _‚d t m t h~ˆ y] d q ] z m Ž h j h~m t h d ˆ„y
q ]cg¨€ t `ad m i{`X_•h¡gd ]cg—] d  ‹` h t €{m t z `Xh#gog `X_ | ` t h ‚`‹_
t h‰] _g ] dWj~] s{t g `] sXXt ]cg ˆ Š `X_X` Ž h#gv] _cdWj~]‚g'€{mcgg m i{]cg

] ¬ €Xj h Š m d}h z g yY` s €Xj s d O
d j~]cg t ˆ h _cd t ` qcs h#gv] _cdOj~ˆ iXh¤d}h Ž ˆcgr€{m t ~j m _aˆ Š ]cgg h d ˆ h _‚d ] t _X] qcs t ˆ Š h¤d y z m%h#g m _‚d
m €X€{m t m$bed t ]9j²l s _ h  ] t g z h Š d}h z—q l#m s d m%_cd—€Xj s g Š ` | ˆ t ] _‚d—] d qc’ _Xm Ž ¡h g m _‚d¨j~m°_Xm t t m d}h~`X_ G\[h~]%_¶€Xj s g yE] _
m _‚d}h Š h €{m _‚d;g s{t j~] z h j qcsrt ˆ Š h d yQj~]cg^`{] sXXt ]‚g q ]cg | h¡gd ` t h~] _{g q ]§“ s X_ ] q `X_•_a] _cdw€{m t z `Xh#g[m s j~] Š d ] s{t s _
m €{] t s q ] j~m z h _  ] t goj‰m ‘cs ] j j~]°d ] _ q j~] t ˆ Š h d yEj=l~h _{g Š t h  m _‚d q m _g s _X]9_aˆ Š ]cgg h d ˆ | h#gd ` t h ‘cs ] yÐj s h


Š `X_ z ˆ t m _cd s Y
_ m‚g €{] Š dËd t m iXh ‘cs ]2] d ` t h‰] _cd m _‚d _a] d=d ] Ž ] _‚d j=l~h _‚d ] t € t ˆ d m d}h~`‹_?c“Ðm _gWj~] Š ’aŠ j~]G…ah~] _ q l¡m s d t ]cg
`{] sXXt ]‚g Š `X_cd t ¤h … s ] _‚d§¯ Š t ˆ„] tFq ]cgF] z=z ] d g q ] t ˆ„] j~yA¯ºg h ŽTs j~] t2s _X]Ïh _‚d ] t d ] ¬ d s m j h d ˆ y ‘cs ] Š ]ºg `Xh d q ]cg
+ =
] ¬ d t m h d g qcsOz `‹j Xj~` t ] z=t ] Ž ] _—` srq ]‚g Š h d m d}h~`X_g q ]Tj~m5\[h …aj~]EƒAm d | `‹j h ‘cs ] t m _•i{] •“Ð] ŽFª Ž ]5d ] j ` s

d ] j7mcg €{] Š d q ] j²l s _ h 
Š `X_g}d ts?Š d}h~`X_ ] drj²l#` t
€{m t d}h Š s j h~] t m s±q ˆ … s d

] t g q ] j²le ~™QšA› œ  #•™ {€ ]
h~] _‚d m d}h~`X_ q ]Sj=l | ` t h ‚`X_
qcsUŠ ’aŠ j~] y«€{m t j~m̀ t ]cg Š

s dMg l#] ¬ €Xj h ‘cs ] t 9
¯ dtm ] tg s _
q l¡m d=d ] _‚d ] qcs j‰] Š d ] s{t ]cgd m
h‰] _ Š ] q ]cg2³Kd t ˆ h q ]cg  kwmY€Xj~m Š ]

q h~m%j~`‹i s ] Y¿ s{t d ` s d yÐj‰m
 m _‚dod ` s dºmcg$g s{t ˆ„]„y¨] _

q ]‚g | #h g}d ` t ~h ] _g q m _g;j‰]
Š ’aŠ j~];_X];€{] s d q `‹_ Š €{mcg t ]‚g$g ` t d}h t s •_ h c‘ s ] Ž ] _‚dW¯ s _X]2mcgd s?Š ];j h d=d ˆ t m h t ] y`X_E_X]K€{] s d q `X_ Š _ h~] tW‘cs l~h j ’
mF¯Td t m  ] t gAj~]cg z h i s{t ]cg q l | h#gd ` t h~]%_ s _X]  `Xj~`X_cd ˆ q ] Í ` s ] t m  ] Š j~m q h#g Š h €Xj h _a] | h¡gd ` t h ‘cs ]„y  `Xh t ] q l#] _
h _‚d ] t t `Xi{] t j~]cg z `‹_ q ] Ž ] _‚d g 
8

:"

% 'H &

+ # %

t ˆcg ]%_cd ] Xq u K
g j~]‚gK€ t ] Ž h~] t g
c‘ s hAg l¡m t t ª d ] t †kwc] g§] ¬ d t m h d g q ]
Ÿ7•£{›Xx t}s j~m _—ƒA` t t h _X`O]cgdwj=l | ˆ
:

¾ s m q l‰“§h … l} ƒ;l#]‚gd[¯Fj~m Š ` s{t
g ]‚gMŒ sXXt ]‚g y¨m s q ] Ž ] s{t m _‚d
…Xh‰`‹i t m%€ | h ‘cs ]cg±] d­m s d `a…ah~`Xi t



,. / % '1* + ' %

Ž •` d g qcsºŠ ’aŠ j~]„yQj~m : t h _ Š ]cg$gv]Ðx ts j~m _—]cg}d'j‰mЀ t ] Ž h u t ] | h#gd ` t h~]%_•_X]Yg s{t
q h ¬ ®_a] s{z;q ]Ïgv]cg2`{] sXX t c] g2m Š„Š ` Ž €{m%iX_X] _‚d Š%| m Š s _ q ]cg Š | m €Xh d t ]cg q ]
t h¤d}h u t ] q ]Ej=l¡] Ž €{] t ] s{t ¿ | m qXq m Ž x65Ey ] dw¯ Š ]5d}h d t ]§ˆ €{` s gv]E` z=z h Š h~] j q ]

h Ž {€ ˆ t h~m%j~]Y] dG¯Ðj²l | h#gd `Xh t ] q ]Yg `X_ Ž m t h
 m t ~h ˆ„]cgG´E` sXat m i{]cg q ] t ˆ z ˆ t ] _ Š ]cg y
m € | h ‘cs ]cg y Š ` ŽEŽ ] _‚d m h t ]cgvy t ] Š s ] h j¡g q

‘cs ¡l ]cgd Š `X_gvm Š t ˆEj=l¡]cg$gv] _cd}h‰] j q ]
t ˆ z j~] ¬ h~`X_g ] d©m _Xm%j ’ g ]cgvyY]cgg m h#g

] Š ‹` _  ] t g m d}h~`X_gvy q ]¶€{m t `‹j~]‚g y
ŽFª Ž ] q ] j~ˆ%i{] _ q ]cg Tx t}s ~j m _ ] j j‰] ŽÐª Ž ] _ l~h _cd ] t h~]%_cd ‘cs ]Id tvu god m t q h  ] Ž ] _‚d q m _gOj=l~h _cd t h i s ]„yF] d
=j l¡m Ž €Xj~] s{t;q ]Ìgv`‹_—`{] sXat ]„y t ] _ Š `X_cd t ˆ„]F¯ Š%| m c‘ s ] Š | m €Xh d t ]„y Š `X_cd t mcg}d ]Fm  ] Š j~] t j~] t ]cg}d t ] h _‚d ‘cs hË]cg}d
Ò L cä ôã Þ¡ìQê ë ¤ì ç¤ç ìµå#ã áÊâ‚×$Þ¡ß å#ì}ä$â ß ì†× ܁Þ
ë ì}é'ô}ã ÿQÿ ìËÜ ÜäÞ•ëäWáÊäâ ßÞ â é á åeâ ã Þ¡á ê ë ì ò}ó â„é Ü å•ÿQë ô=é é á åeâ ãvÞ¡á¤ôÜ ç â Þ~ëâ éWáæäWáÊâ Ü åaõ ì ç ç Ü å

( Q
}
‚

p

t ˆcgv] t  Y
ˆ ¯Ìgvm0€{] t g `X_•_X]7] d'd ` s dA€{m t d}h Š s j h u t ] Ž ] _‚d[m  ] Š j~] ́s i{] Ž ] _‚dA€{` t d ˆÌg s{t ] j j‰]0€{m t C ]‚g$g h Š mF¯Ðj‰m
z h _ qcsUt ` Ž m _ + 7 Q\^] j j~]—€{m d t h Š h‰] _•_a] z ` t Ž ˆ„Ï
] €{m t j~]Ì\^] _X] 8T]cgg ] t h d y'x ts j~m _­m €X€{m t d}h‰] _cd§¯Ïj‰m  h~] h j j‰]
¦
m t h¡gd ` Š t m d}h~] y Ž m h#g ‘cs l¡] j j~];j~] Ž `X_cd t ]2` s _X`X_ n y ]%j j~] z m h dˀ{m t d}h~] q ]cg  m h _ Š s g q ]Kj=l | h#g}d `‹h t ]• d t m  ] t g

¾ s m q ‰l “§h … lµ] j j~]F]cg}d Ž
Š `X_gvˆ ‘cs ] _ Š ] q ]0j‰m q
j=l¡m  m%h _ Š s ]§] d t ] Í ] d ˆ„]

m t ~h ˆ„]E¯2j=l | h#gd `Xh t ] y Ž m h#g q ] Ž m _•h u t ]
ˆ z m h¤d ] q ]cg2g h~]%_g  ¿XhËx ts j~m _rg ] Š X` _g m
q m _{g'j~]T€{m‚g$g ˆ  3wj j~] t ] € t ˆcgv] _cd ];j=l¡m _

Š | cm gd ] yµg}d ˆ t h j‰]„y Ž m t h~m%i{] z ` t Ž ] j ] d z h Š d}h z y
Š t ]Y¯Fj=l | h#g}d `‹h t ] q ]Y g `X_Yd ] Ž € gvy Š ]Td ] Ž € g
Š h~] _•_a] qc’ _amcgd}h~] y‹d ˆ Ž `Xh iX_Xm%i{] q ]cgwˆ Š%| ] Š g

€{mcgg ˆcg^] _ ’ g}d ˆ q m _{gKj~]F€ t ˆcgv] _cd ƒA] c‘ s µ
h m ŽFu _a]Y¯¨g l~h _cd ] t t `‹i{] t
| h¡gd ` t h ‘cs ]F´Q_ l¡m €X€{m t d}h‰] _cd ® ]%j j~]—m j~` t g ‘cs l#¯ Š ] sX¬­‘cs hW_ l¡`‹_‚d t h~]%_
t ] Í ] d ˆcg Gkw] t j~];m d=d t h … s ˆK€{m t j~mTg s h d ];¯Kx ts j~m%_ Š `X_ z h t Ž ] Š ] d=d ]Kh Ž

halshs-00137198, version 1 - 17 Mar 2007

t j~] | h#g}d `
€{] t gv`‹_ _X]

t h c‘ s „] yK]%_°€{m t d}h Š h €{m _cdЯ s _
q l s _ | ˆ t h d}h‰] tAq ]D:µm s j?®«ˆ Š |

‘cs l s Ï
_ €Xh‰`‹_ Ž m _ h € s
q ]9g ]‚gog ] _‚d}h Ž ] _‚d g—] d7¯ s X_ ]
Š `X_gvm Š t ] m s g$g h§j=l#] z=z m Š ] Ž ]%_cd

3wj j~]0_?l#]‚gd

j~ˆ„y s _

g s{t ~j m Š X` _ q ¤h d}h~`‹_ q
q l¡m s d t ]1 Š ] sX¬
m%i{]•¿{mGd ] _‚d m d}h  ]

]Td ` s d ]Fˆ Š t h d s{t ]
‘cs ]Yj=l | h#g}d `‹h t ]¨m

q ] t ] d t ` sX ] tQs _
 mcg}d ] Š ` Ž €Xj‰`ad y[] d q ]o€{` t d ] t j~] z#s d s{tÐq ]Ïj=l¡] Ž €Xh t ]O®E] _Mj‰m
` s ]5_?l#m …{` s d}h#g$gvm _cd ‘cs l#¯;j s h t ˆ  ˆ%j~] t g `X_0€ t `‹€ t ]2m  ] s iXj~] Ž ]%_cd
z m Š d ] s{t^q ]Ìg}d ˆ t h j h¤d ˆ„y q `‹_‚dAj=l¡m Š„Š ]‚g$g h‰`‹_—¯Ej~mE€Xj~] h _X] Š `X_g Š h~] _ Š ]

t ] j~m d}h  ]Mm s d `‹_a` Ž h‰]M]cg}dF€Xj s g ‘cs ]©d m t q h  ] n + «kw] › Ç$Ç  #›r¢{›ÏŸ7•£{›
q ]¶gv`‹_ `] sXat ]F´5j‰]cgrˆ €Xh i t m € | ‚] gMg `X_cd q ˆ‚g ` t Ž m h#g—d}h t ˆcg q l¡m s d ] s{t g
 m t h~ˆcgvy ŽFª%Ž ]Ìg h†d t `Xh#g[_X` Xs  ] j j‰]cg;`{] sXat ]cg q lex t}s j~m _rg `X_cd Š h¤d ˆ„]cg •”W› Ç[˜A£}ÕÂX£?ʼnÇ2¢{›TŸ7•£{›Y_ l¡] _ Š h d ] _‚d
X€ j s g ‘cs l s _X]Yg ] s j~]F] d Š `‹_ z h t Ž ] _‚dKgvmYg h d s m d}h‰`‹_ q ]E€{] t gv`‹_ _Xm i{];…{m j j‰`ad=d ˆT€{m t j=l | h#g}d `‹h t ]„y h _ Š m%€{m …Xj~] q ]
j=l~h _ z j s ] _ Š ] t y0_ h ŽFª Ž ] q ]9j~m Š ` Ž € t ]%_ q•t ]•;x j t ]  h‰] _cdO¯ 8 | m%_•h Ž m q l#] ¬ € t h Ž ] t m … t}s €•d ] Ž ] _‚dO] d
Š j~m%h t ] Ž %] _cdWg mK€Xj~m Š ] z m Š ];¯Kj=l | h¡gd `Xh t ];] _Ej²l#m €X€{]%j~m _cdËx t}s j~m _Ej~mGf s h _a] nXn 
t q
t t h _a` yF€{] t g `X_•_am i{] h Ž €{` t d m _‚d q ]cg¨˜A£}ÕÂX£?ʼnǰ¢{›°Ÿ7•£{›‚y t ] € t ] _ q ~j ]U€ t `a…aj u Ž ]
Ëm m le_ ƒA`
j=l¡ˆ Š t h¤d s{t ] q ]Ðj²l | h#gd `Xh t ]Ej~¯F` ox t}s j~m _og mTd m _‚d ]Tj=l¡mEm …‹m _ q `X_•_aˆ„y ˆ d m _cdw] Ž …Xj~ˆ Ž m d}h ‘cs ] cq s …‹mcg Š s j~] Ž
q ]ºi{ˆ%_Xˆ t m d}h~`‹_ ‘cs h[]cgdÐm s Š `{] s{t7q ]©j²leh _‚d t h i s ]• ¾Um h¡gFh j[m Š„Š ` Ž €Xj h d s _ Š | ] Ž h _U] _°i t m _ q ]o€{m
h _  ] t vg ]• Ëm t m q le_U_ l¡]cg}dF€{mcg Š ` Ž§Ž ]ºx t}s j~m _ s _
³  ] Š js Ë
h j=l#ˆ Š t h d s{t ] q ]Ej=l | h#g}d `‹h t ]E_X]Yg ] Š `X_g}d}h d s
€{`Xj h d}h ‘cs ] ‘cs hËg l¡]cgdµ€{] t qcs ]••³ s̊ `X_cd t m h t ]T]%j j~] q

q ]
] _‚d

t }d h‰]
 m h _ Š s «kw` t g ‘cs leh jKm%€X€{m t m$bed2d ` s dF]cg}d q ˆ Í ¯o€{] t qcs 
]E€{mcgA€{m t[q ˆ z m s d y Š ` Ž§Ž ] s _og s … g}d}h d s d q ]Ðj²l#m Š d}h~`‹_
ˆ z h _•h¤d Ëm t m q le_ n ½ ] d ¯5€{m t d}h twq ]5j~¯;€{] s dwg ];€ t `‹€{` g ] t

Š ` E
Ž Ž ] s _7m  m _‚d m i{]„y s _Fh _{gd ts{Ž ] _cd q ]5j~m Š `X_ ‘cs?ª d ] qcs
t q _ g s{t x t}s j~m _Xy2h jT_?l#]%_cd t ] d}h‰] _cd¸€{mcg q leh j j s g h~`X_·g s{t
Ëm m le·
| ` ŽEŽ ]‚g ÉX•x j€{] s d m h _{g h?m q•Ž ] d=d t ] y z m Š ]2¯5j‰m^d ] _‚d m d}h~`X_ qcs

€{` Xs  ‹` h t g s € t ª Ž ]
j s h~® ŽÐª Ž ]° ] d7€{]
€{` sX `Xh t g s € t ª Ž

n ¥ c³ s d t T
] g s €{ˆ t h‰` t h¤d ˆ
s d q `X_ Š°ª d t ]MÁ ́s i{]
]Eg m;€ t ˆ z ˆ t ] _ Š ]5€{` s{t

q ]

q ]cg
g ]cg

è ã ã îËìâ¤é á¤ôÜ ç ×$é á ç¤ãå#ã ×$é v÷ ցÕNM#O P Ö × Ø Q Q Ø
Ò 6ò G„é ì wå#Ü wåeé ì é Ü åX×$Þ¡ìâ ìä%å#á¤ã ä%åã í•ÜËç áæâ ìÞ¡ÜÞ Qä Ü}â ëÞ#ìØ H‚ìâ‚ë%åXé ã × ìµåeé ìQí áÊä î å å#ã ç¤Ü ôìËáÊä åeë ô=éWâ é áÊä è$å 2 åeé ì ¤ç¤ç é Ü à ìQç¤áÊâ¤â ç ìËì ç å#ì ÷ Ö
ÕNM OAP Ö ×„ Ø Q ù ý„6Ø H ¤áæÿQ× ãvÞ~â ܁ä ô}ì îì ç ¤ã ìë àvÞ¡ì ç¤Ü á å=å#ì î$ß î ë áæÞ¡ì ê ë ¤ì ç ç¤ìä ì}ë$â%× Ü å•ìäµì í í ì}â„è ޡ܁ä îËô é ãå#ì î ¤Üëâ Þ¡ì$Ø
ñ $#Õ M#OAP Ö ×„ Ø Q ú$ú ò ô}ç Üvå=å#á ô{áÊäµáÊâ‰åcé Ü}ë$â ìë$Þ²Ö ë$äâ ã ë ô é ì î†Ý â ì ܁޲å=Ö$ôã ÿQ× ç ì}â ì ç ëä î$ì í ì ܁â ì î$÷Ø
ñ ҕò%ö°åeé ì åeõ ì Ü}Þ=åXåeé ì ç¤ã à ì î é áæÿ¨Üä
î ä ìõFáæâ%ä ã â#Ø "$é ì{Þ#ì à á¤ç¤ì åcé ìÞ " á åeâ ìÞ~é ã ã î$÷vց Õ &EÖ ×„Ø ýý‚ü Ø
ñ ñ ò%öºâ¤é ì ä ܁ÿµì î vãvëËó Þ~ë ç ܁
ä {ޕá å•áæ â Xë áÊä Ü ç #
ö Xë áÊä ãvë åcó Þ~ë ç ܁ä ÷ Ö XÔÕ Ö ×„Ø ý$ú K Ø
ñ ø ò „ÜÞ¡Ü 4î æä ä ìõ7é á åã õ ä«â Ü ç¤ìä$â‰å܁ä î é ì ç¤î«í ì}õ¨á¤ç çæë%å#á¤ã ä%åÜÝ ã ë$â‚â é ìÿ'(Ø ì†õ ÜvåÜ é á åeâ ã Þ¡á Ü} ä " ܁ޡô=é Ü ì ã ç¤ã è á åeâ‚Ü}ä î #ë î$è ì ã í„ÿ ìä Ø ÷ Ö
XÔÕ Ö ×„Ø ý !Ù Ø
ñ û ò}õ áÊâ¤é ã ëâ‚åeë ô éµáÊä í ã ÞeÿµÜâ á ã ä%Ö$ã ä ì ôÜ}ä$ä ã â è ã à ìÞ~ä Ø ÷ Ö XԁÕWÖ × Ø%6ü K ù Ø




!#" !$ % &' % ( )' *
<

t ] %Š | ] t Š%| ]cg | h#gd ` t h c‘ s c] g
t ˆ„m%j h#gd ]‚g n À{Q¹F` ŽEŽ ]Om =d d m
j=l | h#g}d ` t h~] _—´ j~]cgEj h Xt ]‚gE_X`

] d =j l¡] ¬ ] t Š h Š ] q ] t ]cg €{`‹_{g m …ah j h d ˆ‚g €{`Xj h d}h ‘cs ]cg €Xj s g j h Ž h d ˆ„]‚g ] d €Xj s g
Š | ˆom Xs ¬ j h at c] g§] d2¯og ]‚g0gv` s{tvŠ ]cg yN Ëm t m q l~_ ]cgd Š `X_g Š h~] _cd q c] g2j h Ž h¤d ]cg q ]
s g§m €X€ t ] _ _X] _‚d ‘cs ]¨j=l¡`‹_r€{] s d z m h t ] Š ] t d m%h _X]cg Š | ` gv]cg y Ž m h#g2~j ]  ˆ t h d m …Xj‰]
p
m €X€ t ]%_cd}h#gg m i{]F_X]  h~] _‚d ‘cs ] q m _{gKj‰m t ˆ„m%j h#g m d}h~`‹_ n X¼Ym t t m d}h~`X_O] d[m Š d}h‰`‹_ q h z=z}u t ]%_cd ]cg$gv] _cd}h~]%j j~] Ž ]%_cd y
j~]Ed t m  m%h j q ]Fj=l | h#gd ` t h~]%_Ï_a]Ðd t ` sX ]¨g m  m j~] s{tA ˆ t h d m …Xj‰] ‘cs l¡m s gv] t h Š ] q ]Ej~mYg ] Š `X_ q ] ‹kw]  ˆ t h d m …Xj‰]
g m  `Xh tK| h#gd ` t h ‘cs ]¨g ] t m%h d[m j~` t g^] _Om Š d ] q m%_g[j=l#m Š d}h~`X_π{`Xj h d}h ‘cs ] ‘cs m _ q h jQ_?l#]cg}d Š `X_cd ] _ s yQm sOŽ h~] sX¬ y

halshs-00137198, version 1 - 17 Mar 2007

‘cs ¡l ] _°€ s h#g$gvm _ Š ] q m%_gFj=l¡`] sXXt ] q ]oj=l | h#g}d ` t h‰] _ N Ëm t m q l~_
Š ’aŠ j~]—m €X€ t ` z `X_ q h t F
m ´Qj~m Š ` Ž € t ˆ | ] _g h~`X_ q ]Yj=l | h#g}d `‹h t ]Y_ l¡]
qc’ _Xm Ž h ‘cs ]• 3Wd[€{` s{t d m%_cd Ëm t m q le_o_a] t ˆ s gg h d[i s?u t ]Y€Xj s g

z ` t ŽTs ‰j ] Š ~j m h t ] Ž ] _‚d
¬ h#g}d ] ‘cs l#]%r
_ m Š d ]„y Š `
q m _g^j~m Š `X_ ‘cs?ª d ] qcs

Š ] c‘ s Ï
] j‰] t ]cg}d ] qcs
Ž Ž ] s o
E
_ € t ` Š ]‚g$g s g
€{` sX `Xh t g s € t ª%Ž ]„y

ŽFª Ž ]Ìg hWg `X_oˆ Š | ] Š ]cgd Ž ‹` h _g^m Ž ] t  ¿{]cg Š `‹_ _Xm h#gg m _ Š ]cg t ]‚gd ] _‚d'j h Ž h d ˆ„]cg ‹“Ð]cg z ` t Š ]cg | h#gd ` t h ‘cs ]cg
…Xh‰] _Y€Xj s gw€ s h#g$gvm _cd ]‚g y h _ Š m t X_ ˆ ]cg'€{m t kw] d `Ìx x y ] d ‘cs leh j{_ l¡m  m h d €{m‚g  s ]„y t ]%€{` s gg ] _‚d'g ]‚g«€Xj‰m _g Xƒ;l#]cg}d
¯ Š ] d=d ]2m s _X] Š ] €{] _ q m _cd ‘cs l#]‚gd Ž ]cg s{t ˆ ]T] d t ] Š `X_•_ s ]5j‰m  m j~] s{twq ] †m t m q l~_—´ckw] d `Yx x t ] Š `‹_ _Xm$b~d«gv`‹_
d m j~]%_cd q l | h¡gd ` t h~] _ayTj s h
€{mcgg ˆ n <  †m t m q l~_r€{] s d

Š ‹` _ Š ˆ q m _‚d s _Si{ˆ _ h~]9m s d | ] _‚d}h ‘cs ]9¯Mj h t ]Mj~]M€ t ˆ‚g ] _‚d q m%_g¨j~]‚gYd ] t Ž ]‚g qcs
z h _am j~] Ž ] _cd[d t ` sX ] t g m¨€Xj~m Š ] t ˆ„] j j~]„y'] ¬ ] t m%_cdEgv]cg Š m €{m Š h d ˆcg§m s € t ` z h d qcs

t€ ` Í ] d q ]±kw] d ` Ž m%h#gr] _ j s h t ˆ‚g h#g}d m _cd ‘cs `•d}h q h~] _ _X] Ž ] _cd yEh _‚d ] _gvˆ Ž ] _‚d yE] ¬ ] t m _‚d s _X]°h _ z j s ] _ Š ]

Š
s
Š
q
t
Š
t
Ž
q
Š
{
s
t
Ž
s
h _am d ] j j‰]„y l#]cg}d ® ¯„® h ]¨m iXh#gg m _‚d `‹_‚d ]Yj~]0d ] € gvy `X_ g j~]0d ] € gvy«m …‹ˆ _Xˆ z h Š ] q l s _¨d ] Ž € g^¯
 ]%_•h t y¨€{` s{t €{m t m € | t mcg ] t ¼0h~] d •g Š | ] n = F³  ] Š·Š ] d=d ]C€{` g h d}h~`X_ m Ž …ah i s Cq ] Š `‹_‚d t ]„®€{` sX `Xh t m s

g ] t  h Š ] cq s {€ ` sX `‹h t Ëm t m q le_Fi{m iX_a]K_Xˆ„m%_ Ž `Xh _g Š ] ‘cs lex ts j~m _E_?l#m  m h d Í m Ž m h#g t ] s y s _X]K€{` gd ˆ t h¤d ˆ„y s _
q ]cg}d}h _ z ˆ Š `‹_ q y Ž m h#g Š m Š%| ˆF´ Š l¡]cgdwj s hË] dw_X`X_Ykw] d `Ïx x[® q ]  ] _ s h _ |‚s{Ž m h _—® ‘cs h Š `X_cd}h _ s ]Ej~mEj h iX_Xˆ ]
m d t ˆ%h q ]••³;j~` t g ‘cs l~x ts j~m _ t ] Š ]  m%h d j~]Eg s{t _X` Ž Ž ` ‘cs ] s{twq ]5Á%j~mKf s h _X] É y- Ëm t m q le_F]‚gd …{m €•d}h¡g ˆ q ] Š ] j s h

q ]º¹Ðm t ‘ m j‰®³ q „m yKj~]rÁ \
Š `X_•_am h#g$gvm _ Š ] qcs {€ mcg$gvˆ
|cs{Ž m _•h d ˆ  †m t m q l~_¨` z=z=t ]

t #h gv] s{t¨q
‘cs l~h jW€{]

l | m …Xh d s?q c] g ÉX;¿XhG…ah~] _ ‘cs º
] j=l¡`‹_U€{] s d7]‚gd}h Ž ] t¨‘cs ] Š l#]cg}d q m _{gÏgvm
s d;€ s h#gv] t ~j m z ` t Š ]—] d^j~m Í}s g d}h z h Š m d}h~`X_ q ]og `X_ `‹€X€{` g h¤d}h~`‹_ay q ]Ïgv`‹_
q X` _ Š m%€ t u g'j‰m z h i s{t ] q l~x ts j‰m _Xy s _X] z h i s{t ] q l | h#g}d ` t h~] _0…ah~] _F€Xj s gW€{` g h d}h  ]„y
ŽFª Ž ] g h Š `X_cd ]%_ s ] q m _gUj~]cgUj h Ž h d ]cg q ] g `X_ gvm  `Xh t ] d q ] g `X_ |cs{Ž m%_•h d ˆ• :µ] s d ® ª d t ]·]cgd ® Š ]
€ t ˆ Š h#g ˆ Ž ] _cd Š ] ‘cs h z m h¤d«gvm  m j‰] s{t y Š m t g ]‚g j h Ž h¤d ]cg'g `X_cdµm s gg hXj~]‚g Š `X_ q h d}h~`X_g q ]Tg `X_F` sX ] t d s{t ]
ƒA]M_ l¡]cgd ‘cs l¡¯ºj~m z h _ q ]‚gT˜A£}ÕÂX£?ʼnǗ¢{›ÏŸ7•£{› ‘cs ]rj~]ºj~] Š d ] s{t¨Š ` Ž € t ] _ q ‘cs ]rj~]cg7_X` Ž … t ] s g ]cg
ˆ €Xh i t m € | ]cg[g h iX_aˆ„]cgW¹Fm tv‘ m j~®³ q 0
m gv`‹_‚d q c] gA] ¬ d t m h¤d g q ]Tj=l~Œ Xs Xt ] q ] Ëm t m q le_ t ˆ q h i{ˆ„]2m € t u W
g j~m z h _ cq s
t ˆ Š h d ³;j~` t g ‘cs l~x ts j‰m _o]‚gd;g s{t d ` s d s _X] Ž ˆ Ž ` t h~m j h¡gd ]„y t ˆ q h {i ]„m _‚dAj=l | h#g}d `‹h t ] q Y
] g `X_Yd ] Ž € gvy Ëm t m q el _

ñ þAò ã õ°Üâ¤â¤Þ#Ü ô â á à ì[áÊâ Þ¡ìÿ Ü áÊä ì î ֋â¤é ìAë$Þ¡è ìGâ ãKÞ¡ìâ áæÞ¡ìKí Þ¡ã ÿ°â¤é á å è ܁ÿµìGáæä$â ãGé á åQ×$Þ¡ì í ìÞ~Þ#ì îK×$ë$Þ²åeë áÊâ‰å " é á åeâ ã Þ#á¤ô}Ü çÞ¡ì å#ì ܁ޡô=é2܁ä î
ç¤ì ܁Þ~ä áæä è â é ì ÿµÜä á¤í ì åeâ î ë$â á¤ì å‹í ãvÞ Þ~ë ç¤áÊä è†é ì}Þ#ì ã ä " Ü çÊë å#
Ü " ì ô ëä î ë%åØ ÷ Ö XÔ}ÕWÖ ×„Ø%ü.Kvú 2$ò}ó æÿ¨è ã áæä è Ý Ü ô Qâ ã ÿ Ý ã ã+ å•Üä î â é ì ã â é ìÞ
×$ëÞ²åeë áæâ~åcõ é á ô=éQé ã ç î ÿ ã Þ¡ì áÊäâ ì}Þ#ìvåeâ„í ã ނÿ ìØ ÷ Ö XԁÕWÖ × Ø% ü ' ú„Ø
6ñ E'ò%öKã ä ì'ç ì ܁Þ~ä%åQí Þ¡ã ÿMÝ ã ã åQ܁ä îAÞ#ì ì ç åQã ä ç 'â¤é Ü}â ô}ìÞ~â Ü áÊä[â é áÊä è$åQô}܁ä[Ý ì'îãvä ì$Ø ô â¤ë Ü ç{ç¤ì ܁Þ~ä áæä è«Þ¡ì ê ë áæÞ¡ì å â¤é ܁â vãvë[îã«â é ãå#ì
â¤é áæä èåØ ÷ Ö XÔ}ÕWÖ × Ø ý ! ü ò%ö â é ìÞ¡ì õ Ü å†ÜWî$ì ì}×Kì}ÿ ã â á¤ã ä Ü ç î$á¤í í ìÞ¡ìä ôìQÝ ìâ¤õ ì ìä'é á åeâ ã Þ WÜ åÞ#ì ôã Þ¡î$ì
î #
ö X܁ä î«â¤é ìQé á åeâ ã Þ õ é á¤ô é
ã ä ì ç¤á¤à ì î$÷ Ö XÔ}ÕWÖ ×„Ø%ü}Ù ú„Ø
6ñ FËòó
â #
ö í ç Ü}â â ìÞ¡ì î ã ë$ÞXÞ¡ì Ü ç„â Ü ç ì}ä$â‰Ö õ é á¤ô=éWá å•â é ܁â‚ã í„é á åeâ ã Þ¡á¤Üä„Ø
ã ë ¤à ì ܆îì í áæä áæâ ì è ìä áÊë å‹í ã Þ Þ#ì Ü î$áæä è â é ì אޡì å#ìä$â áÊä â ìÞ~ÿWåXã í
â¤é ì× Ü åeâ#Ø
?ãvë ¤à ì?܁ä$â á ô}áæ× Üâ ì î†ÿµì ã äWå#ì à ìÞ¡Ü ç%ã ôô}Ü å#á¤ã ä%åØ ÷ Ö XÔ}ÕWÖ ×„ØÚ AÙ K Ø

( Q
}
‚
=

]cg}d;m s g$g h s _©m _cd}h ‘cs m%h t ]0d ` s{t _Xˆ  ] t ;
g j~]Y€{m‚g$g ˆY€Xj s g2` s Ž `Xh _{g t ˆ Š ]%_cd y s _rm t Š | ˆ„`Xj~`‹i s ] ‘cs hË_X] z#s h d
€{mcgUg `X_ € t ˆcg ] _‚d¨¿ leh j¸ˆ Š t h¤drj=l | h#g}d `‹h t ] q ] kw] d ` x x yYh jÏgv] Š `X_gvm Š t ] m s g$g h¨¯Sj~m9…Xh~`Xi t m € | h~] q ]
€{] t gv`‹_ _Xm i{]‚go€Xj s g©m _ Š h‰] _g Š ` Ž§Ž ]±kWh~] d ® ’ _a]cgr] d ŽFª Ž ] ¯Uj=l | h#gd `Xh t ]U€Xj s goj~`Xh _‚d m h _X] qcs C$h | m q

t q
\ s }d j~ˆ t h‰] _o] d q ]0j=l ;i{] q l¡` K
€{m tAŠ `‹_‚d t mcgd ]§] d z h j h~m d}h~`‹_¸m  ]
q ]cg z h i s{t ]cg2g s h  m _‚d ]cgA_ l¡` Š Š s

]Ej~mFÑW] t t ] ‹¹§h#gd `
Š x t}s j~m _Xy{h j ]‚gd j‰m

t h~] _
z h i s{t

Š ` Ž X€ j‰] d y†€{] t g `X_•_Xm%i{] t h Š | F
] ] dw€{` g h d}h z yˈ j~m …‹` t ˆ
] q l | h#g}d ` t h~] _Fj~m;€Xj s gwm …{` s d}~h ] qcs—Š ’aŠ j~] y m s?Š s _a]
_X]Td ] j j~]Eh Ž {€ ` t d m _ Š ]•x j h j j s gd t ] q `X_ Š €{m t z m%h d ] Ž ] _‚d'j‰mЀ{` g h¤d}h~`‹_
ŽFª Ž ]©g h«h jW_ l¡] _ q `X_•_X]¨€{mcg;d ` s gTj‰]cg q ˆ  ] j‰`‹€X€{] Ž ] _cd g Q³ s g$g h

€{m _cd s
q ]Ïj=l | h¡gd `Xh t ] q m _{gEj~] Š ’aŠ j~]—] _cd}h~] t y
Ž Ž ] _‚d q m _{gTj‰] Š ’aŠ j~]„y j~]cg | h#gd ` t h~]%_g2] d[j~] {s t2q h#g Š h €Xj h _X]Ïgv`‹_‚d
€{] s d ® `X_Xyw¯Ì€{m t d}h tEq ]¨j s h~y Ž `‹_‚d t ] t§Š ` E
Š m _‚d `‹_ _Xˆcg ¯ s _F]cg €{m Š ] q h z=z h Š h j~]„yXj h Ž h d ˆK€{m tWq c] g €{m t m q h i Ž ]cg Š `‹_ Š s{t t ] _‚d gW` s g s €{ˆ t ~h ] s{t g 

: " + # + % / + % % * + ' % &(* % / +% / % % 1 1 % ' %„V
‡
q
t
q
s{tÏs _ Š ] t d m%h _¶d ’ €{] q l~h _ z ` t Ž m d}h~`‹_ayEj=l#mI] _cd t mb#_XˆUm sX¬ j h Ž h¤d ]cg q ] vg m
kw]9i{` d ] Ë
m m el _ €{`
q #h g Š h €Xj h _a]F´•j~m5€Xj‰m _ u d ] q ]  ~h ] _cdµ`•… Í ] d q l | h¡gd `Xh t ] Ž m h¡gWm s g$g h g s%Í ] d•ƒA`X_g h q ˆ t m _‚dQj‰mGd t u g j~`X_•i s ] qcs{t ˆ„„] y
t q
s{t j~] q ˆ d ] t Ž h _•h¡g Ž ] qcsIŽ h j h~] s yKm i{] _‚d Š ` Ž €Xj‰] ¬ ]„yA€{]cg m%_cd2h _ q h t ] Š d ] Ž ] _cdFg s{t j~]cg
Ëm m le_°h _g h¡gd ]Mg
7
m Š d ] s{t g q ]0j²l | h#gd `Xh t ]„y ¯Fj~m Ž m _•h u%t ] q l s _ºg}d ’ j~]„y q l s _Ï ~£
„Ä•£XÇ „ ¡› £?Å n “Ðm _{g Š ] d=d ]0€{] t g €{] Š d}h  ]0€Xj s g

halshs-00137198, version 1 - 17 Mar 2007

8



% + 1 % %

‘cs ]K… t m s?q %] j h~] _ _X]„yj²l | h#gd `Xh t ]2]cgd Š `X_ qcs h¤d ];¯Tg l¡] z=z m Š
¯¨j~m©g Š h~] _ Š ] t ] h _a] q ]TŸY•£{›‚y j=l¡ˆ Š `Xj~`XiXh~]• kwm0d t m _g
m Š d ] s{t g |cs{Ž m h _g§¯Ìj‰] s{t h Ž € s h#g$gvm _ Š ]„y'¯¨j~] s{t h _ Š `

¦
] tWq ] t t h u t ]Kj~mK€Xj~m _aˆ d `‹j‰`‹iXh~] ½ y q ] Š ˆ
z ` t Ž m d}h~X` _ q ]Yj~mY€Xj~m%_ u d ] t ]%_  `Xh d[€{]
Ž € t ˆ | ] _{g h~`X_ †kw] q ˆcgvmcgd t ]¨_ l¡]cg}d2ˆ 

q ] t ~j mK€Xj~m Š ]
s ¯Y€{] s j~]cg

h d ˆ c‘ s Y
] €{m t
kw] d `Cx xvy ‘cs hT_?l#ˆ d m _cd¸€Xj s g |cs{Ž m h _XyT€{] s d¸h _ Š m t _X] t j=l#ˆ Š ` g ’ gd u Ž ] q ]Mj‰mM€Xj~m _ u d ]• k[l¡m _ Š h~] _S ] dYj‰]
_X` sX ] m s g l¡`‹€X€{` g ]%_cd ] _ z `‹_ Š d}h~`X_ q ] gvm d t m _{g z ` t Ž m d}h~`X_XyUj=l#]%_ Í ] s ˆ d m _‚d q l¡] _ Š ` Ž € t ] _ q•t ]
€Xj~] h _X] Ž ]%_cdWj~]cg Š `X_g ˆ ‘cs ] _ Š ]‚g ck[l | h#g}d `‹h t ]5€{] t q gvmÐg €{ˆ Š h z h Š h d ˆ„y  h~] _cdwg ] q h j s ] twq m _{g«j‰m5€Xj~m%_Xˆ d `Xj~`XiXh~]„y
j=l¡ˆ Š `Xj~`XiXh~]„y q `‹_‚dKj‰]Y€ t `‹i t m ŽEŽ ]¨]cg}d Š `‹_ _ s­q ]cg;j‰] Š d ] s{t g^€{` s{t m  `‹h t ˆ d ˆ¨] ¬ €{` g ˆ y q m _{g;j~]F€ t ] Ž h~] t
j h at ] qcs—Š ’aŠ j~] y€{m t ~j ]Ðg €{] Š d t ] qcs
q ]Mg ]cg7m Š d}h~`X_g q m _{F
g j=l#m%€X€{] _ q h Š
€ t `Xi t u gvy q ]Yj~m Š `‹_ _Xm h#gg m _ Š ]¨] d

€ %u t ] q ]KkWh~] d ® ’ a_ ]cg ½
]©x7¯0Ÿ7•£{›7´ t ˆ Š h d q

+

 : m‚g$g m%i{] ‘cs ~l h j z m s dËj h t ];] _ t ] i{m t qFqcs7t ˆ Š h d
l s _ Ž ]‚g$g h‰m _•h#g Ž º
] g Š h~] _‚d}h z h ‘cs ]„y q ]Ïj=l~h q ˆ„] q ]
q ]Fj~m Ž m$bed t h#gv] q ]cg q ˆ d ] t Ž h _•h¡g Ž ]cg[_Xm d s{t ] j#g k[l | h#gd `Xh t ]„yQ_am t t m d}h~`‹_
qcs €{mcg$gvˆ¶] d Š ` Ž € t ˆ | ] _{g h~`X_ qcs € t ˆcg ] _‚dr¯ j~m j s{Ž h u t ] q ] Š ] €{mcg$gvˆ„y Š u„q ] j~] €{mcg q ]  m _cd s _
€{m t m q h i Ž ] Š `X_ Š s{t t ] _‚dI] dI] _•iXj‰`a…‹m _cd y Š ] j s h q ] j=l¡ˆ Š `Xj~`XiXh~]„yÏj~]‚g m Š d}h~`X_g q ]cg | ` ŽEŽ ]cgU€{mcgg ˆcg
g l¡] z=z m Š ] _cd q ]  m _cd s _ q ˆ d ] t Ž h _•h¡g Ž ]o…Xh~] _U€Xj s g  mcg}d ]•«k[l¡`] sXat ] q ] Ëm t m q le_°d ˆ Ž `Xh iX_X] q ] Š ] d=d ]
s{t j²l#] ¬ h#gd ]%_ Š ] q l~h _ z j s ]%_ Š ]cg
h _ Š j s g h‰`‹_ q ]ºj=l | h¡gd `Xh t ] q m%_g7j~m cq ’ X_ m Ž h ‘cs ]o€Xj~m _aˆ d m h t ]  w
3 j j~]oh _g h#gd ]Mg

ñ L Ø Qá¤ìâ å#ô=é ì Ö XÔ O1 , ( 0 1 /). ¤Ô#O O(/ . M P, P P . Ö â¤Þ}Ø í Þ}Ø Ø Xë å#ô é Ö Ü}Þ#á å=քü '('vý Ö ×„Ø('vú Ø
ñ [ò öAâ é ìKáæä í çæë ìä ôìAã í Ü'× ç¤Üä ìâ?ë$× ã ä;â¤é ì'ÿ Üvå=åµëä ô}ãvä å#ôá¤ã ë%å ã í†áæâ‰å áæä$é ÜÝ áæâ Ü}ä$â‰åµé Ü åµä ì à ìÞQÝ ì ìä2í ë ç ç [܁×$אޡì ôá¤Üâ ì î$÷vÖ* XÔ}ÕWÖ
ׄØ%.ü K ù%Ø
ø $ ò} ó ¤à ìÝ ì ìäQÞ¡ì Ü îáÊä è ÜÝ ã ë$â%â¤é ì áæÞ ç¤Üä ì}â ã ç¤ã è á åeâö[÷ Ö XÔ}ÕWÖ ×„Ø%ü}Ù Ú Ø
ø ÒX6ò G„é ì é á è é ìvåeâ‚í ë$ä ô â á¤ãväWã í‚ì ô}ã ç ã è Ëá å•ë$ä î$ìÞ²åeâ ܁ä îáÊä èQô}ãvä å#ì ê ë ìä ô}ì å Ø #
ö 2ì ܁ޡì è ìä ì}Þ#Ü ç á åeâ~å ¡ö G é ì×$é å#á¤ôÜ ç%ê ë Ü ç¤áÊâ á ìvå•ã í Ü
× ç¤Üä ìâ„Ü}Þ#ì{õ Þ¡áÊâ¤â ì}ä áæä$â ã†áæâ‰å•ì ôã ä ãvÿµá ô{܁ä î†× ã ç¤áÊâ á¤ôÜ ç Þ¡ì ô}ãvÞ¡î÷ ցN
Õ M#O P Ö × ØÚ ü= ú "~Ú%6ü K Ø




!#" !$ % &' % ( )' *
g s {€ ˆ t h~] s{t ]‚gSˆ  h q ] _cd ]‚g ½ n yMg s{t j‰m Ž m%_•h u t ] q `X_cd­j~]cg Š | m%_•i{] Ž ]%_cd gU€Xj~m _aˆ d m h t ]‚g ] d
ˆ Š | m €X€{] _‚d ¯Kj²l#ˆ Š%| ] j j‰] |cs{Ž m h _X];] dµ¯Tg m Ž ]cg s{t ] y‹j~mKi{ˆ%_Xˆ t m d}h~`‹_ ½X½ 
¾Um h¡gEj~mÏj‰] `X_ qcs g €{] Š d t ]ºg l#m Š%|Xu  ]om ŽFu t ] Ž ] _‚dA´Qj~]‚g0g Š h~] _‚d}h z h ‘cs ]cg§`X_cd[d ` t d yWj~]cg2€


¥
€Xj s gI€{] t Ž m _a] _cd g q m _gIj=l s _•h  ] t gCgv`‹_‚dUj=l¡m Š„Š h q ]%_cdI] dUj=l¡] t t ] s{t ½ ¨x j
j=l¡m €X€ t ] _ •q t Y
] ¯ Ëm t m q le_—´ j=l | h#g}d `‹h t ] |‚s{Ž m h _a]Y]cg}d  `Xj~m d}h j‰]„y  s j _Xˆ t m …Xj~] z m Š
j~] q ` Ž m h _X] q ]Ïj‰mπ{`‹j h d}h ‘cs ]o` Uj~]cg t m h#gv`‹_{gTj‰]cg2€Xj s g2h _g h iX_•h z h‰m _cd ]cgFgv] Ž
j=l¡mcg Š ] _g h~`‹_I] dFj‰m Š |‚s d ] q c] gFi{` sX ]
Š `X_gvˆ ‘cs ] _ Š ]cg y j~]T€ t ] Ž h~] t q #l ] _‚d t ]E]
Š j~m%h t ]U¯±j=l¡m _a] Š„q `•d ] ‘cs h2h j j s g}d t ]„y q

7

Š j h Ž m d}h ‘cs ]cg
t h _ Š h €{]cg2j~]cg
t ª„Š | ] s{tIq ]

t ]  ~h ] _‚dIm s :
]0m so| mcg m tvq y g s{t d ` s d q m _g
…Xj‰] _cd Š ` Ž§Ž m _ q ] t €{m t z ‹` h#g
t _Xm _‚d g  kw] : t ª„Š%| ] s{t j h#g}d ] q h z=z ˆ t ] _‚dE€{] d}h d g z m h d g7m sX¬ i t m _ q ]cg
sX¬ ˆ d m _‚dWj~m q h#g € s d ] q ] q ] sX¬¸z ] ŽEŽ ]cg ½ À{{ƒ5l¡]cg}dWj~¯ s _X]§m j j s g h~`‹_
]%€ s h#g15E`Xj d m h t ]°m s Ž `‹h _g y Š ]M€ t `•…Xj u Ž ] | h¡gd ` t h ‘cs ]„yEg ` sX ] _‚d

p
Á qcs  ] t t ] q l¡]„m s É ½ 2³ s €{m t m q h i Ž ] q ˆ d ] t Ž h _•h¡gd ] ] drg Š h~] _‚d}h#gd ] q ]
t m q h i Ž Ï
] m%j~ˆ„m d `Xh t ]„yWh _cd s h d}h z y Š ] j s h q ]¨j~m̀{`Xj h d}h ‘cs ]„y'¯¨j~mÌ_aˆ Š ]cgg h d ˆ—] d5¯
j=l¡` tvq•t ]M_Xm d {s t ] j~yEg l¡`‹€X€{` g ]Mj~] | mcg m t q ] d7j=l#m … g s{tvq ]„y^d ` s d¸m s g$g h;_Xm d s{t ] j ;m s·q ˆ d ] t Ž h _ h#g Ž ] q ]ºj‰m
~j `X_•i s ] qcs{t ˆ„] y s _ Ž h Š%t `® q ˆ d ] t Ž h _•h#g Ž ]E€ t ]cg ‘cs ]2h _gvm h#g h¡g$g m …Xj~]• Š `X_ q h¤d}h~`‹_Fd ` s d ] z `‹h#g q ]T_X]2€{mcgKgv]
z m h t ] q l~h j j s g h~`X_og s{t j~m  m%j~] s{tAt ˆ„] j j~] q ] Š ]cg[m _Xm%j~`‹iXh‰]cg yË`‹_¨€{` s{t t m h¤d  `‹h t[q m _{g'j~]2€ t ] Ž h~] t € t `•…Xj u Ž ]

halshs-00137198, version 1 - 17 Mar 2007

Š `X_•_ s ] Š ` ŽEŽ ] j²l | h#gd `Xh t ]
j=l¡ˆ Š `Xj~`XiXh~]„yKg l¡`‹€X€{` g ] s _r€{m

j=l¡m €X€Xj h Š m d}h~`X_ cq s € t
q `Xh d«d t ` Xs  ] t g E
m €Xj~m
m s d `X_X` Ž ]°] d q ¡l m s
Ž …{`‚bed ] Ž ]%_cd q ]cg
3

h _ Š h €{] q l~h _
Š ]F] _‚d t ] q

Š ` Ž X€ j~ˆ d s?q E
] ] d q m%_g'j‰]Ðgv] Š `X_ qYqcs € t h _ Š h €{] q leh _ Š ] t d}h¤d s?q ]•ck[l |
] sX¬ € j~]cg ‘cs h j s h Š `‹_‚d ]cgd ]%_cd q l s _X]T€{m t dAg `X_ Š m t m Š d u t ] q ] q h#g
d t ]M€{m t d—gvmº€ t ˆ d ]%_cd}h~`X_ ¯ m €X€{` t d ] t¨q ]rj=l~h _cd ] j j h iXh …ah j h d ˆ m sX¬ m z=z m h t ]cg |cs{Ž
ˆ Š | ] j j~]‚g d ] Ž €{` t ] j j~]‚g ] dCg €{m d}h~m j‰]cg y Š ` Ž € t ˆ | ]%_g h‰`‹_ ] d gd m d s d q ]cg

h#g}d `‹h t ]

Š h €Xj h _a]
m h _X]‚g 
Š m s g ]cg

| h¡gd ` t h ‘cs c] gvy †m t m q l~_9g l#m z=z=t `‹_‚d ]o¯ ‘cs ] j ‘cs ]‚g ® s _{g q ]cg§€Xj s gEh Ž €{` t d m%_cd gE€ t `a…aj u Ž ]cg q ]Ìj‰m Ž ˆ d | ` q ]
| h¡gd ` t h ‘cs •] Tk[l | h#g}d ` t h~] _ q `‹h d©_Xˆ Š ]‚g$g m%h t ] Ž ]%_cdOj~]cg t ˆcgv` s?q•t ] q m%_g°g `X_Cd t m  m h j q ] z h i s{t m d}h‰`‹_ ] _
m ́s g}d m _cd j~]cg z m h d g^] dAj=l¡] ¬ €Xj h Š m d}h~`X_O] d;g ` t d}h t m h _{g h q l s _X]¨g h d s m d}h~`‹_ q l¡ˆ Š m t d u j~] Ž ] _‚d[] _‚d t ] s _ Ž m Š t `{®
_•h  ]„m s ` Uj=l#] ¬{Š„u g q ] Š `
Š `X_cd t m%h t ]Kj=l¡] ¬{Š u g q ~l h _ z ` t Ž
¾Um h¡g y;] d Š l#]cg}dFj~]r€ t h 

Ž € t ˆ | ] _g h~`X_°m €X€{m Xs at h d2j=l~h _ z ` t Ž m d}h~`X_°] d s _ Ž h Š t `{®_ h  ]„m s ` sIŠ l¡]cg}d§m s
m d}h‰`‹_ ‘cs h t}s h _X]Kj~m Š ` Ž € t ˆ | ] _{g h~`X_X½ < 
h j u i{] q ]rj~m±g Š h~] _ Š ]„® z h Š d}h~`X_Xy
Ëm t m q le_Sg ]od t ` Xs  M
] m s g$g h Š `X_ z=t `‹_‚d ˆº¯ q ]cg
€ t `•…Xj u%Ž ]cg—g €{ˆ Š h z h c‘ s ]cg¸¯±g `X_ s _•h  ] t g AƒAm t j=l | h#g}d `‹h t ] q `Xh d7m s gg hTgv] ́s g}d}h z h~] t y q m _g7j=l s _•h  ] t g q ]
“ s _X]„y z m Š ;
] ¯ q ]cg €{m t m q h i Ž ]cgwg s €{ˆ t h‰] s{t g[´ q l s _X]K€{m t dËj~m Š `X_•_Xm%h#g$gvm _ Š ]K€ t ]cg Š h‰] _cd ] qcs7z#s d s{t i t Š ];¯
j~mMd t m _{g ] q ]±j=l¡ˆ €Xh Š ]9] d q l#m s d t ]±€{m t d¨j~m Š `X_•_am h#g$gvm _ Š ]9ˆ d ]%_ qcs ] qcs €{mcgg ˆ°i t Š ]U¯Mj~m Ž ˆ Ž `‹h t ]

ø ñ ò%öMã Ý à á¤ã ë%åcé á è é ì}Þ " ãvÞ¡îìÞ áÊä í çÊë ìä ô}ì å•áæä ܁ä × ç¤Üä ìâ Ü}Þ †å åeâ ì}ÿ ÷ Ö XÔ}ÕWÖ ×„Ø ý K Q Ø
ø ø ò%öGâ¤é ãå#ì ç¤ã ä è î Þ¡á¤í â‰å•ã í ô é ܁ä è ìõ é á ô=é Ü?è ì}ä ìÞ¡Üâ á ã äËÿ Ü í Ü á ç â ã ä ã â á¤ôì ÷ Ö XԁÕWÖ × ØÚ ü Ú Ø
ø û 6ò G„é ì}ä%Ö Ü åaé á å•× ç¤Üä ìâ á¤ç¤ç ì î é áæÿWÖ$áæâ„ã ô}ô ëÞ~Þ#ì î†â ã ä ì åcâ¤é Ü}â é á å•í Ü}â é ìÞ ܁ä îËÜ ç ç â¤é ì ã â¤é ìÞaå#ô}á ìäâ á åeâ‰åcõ ìÞ¡ìõ Þ¡ã ä èÖ â¤é ܁â%â é ìÿ ãåeâ
× ì}Þ=å#á åeâ ìä$â%×$Þ¡áæä ô}áÊ× ç ì å•ã í â¤é ì{ë$ä á¤à ìÞ²å#ìõ ìÞ¡ì Ü ôô}á îìä$â ܁ä îQìÞ~Þ¡ã ÞØ ÷vցN
Õ M#O P Ö × ØÚv ý !%Ø
ø þ ò ;é ܁â åeÿ Ü ç¤ç%ì à ìä$â‰å ä Ü}Þ#è ëÿ ìäâ Ý ìâ õ ì ìäQâ¤õ ã õ ã ÿ ì}ä•ö[÷ Ö XÔÕ Ö ×„ Ø K ù%Ø
6ø E # í¡Ø Ø " â ìä è ìÞ²å=$
Ö AP 1 .
P P ( .¤Ô 1 P O + - P 2 ( . Ô 1 P / M 1 ( M P AM / / 1 Ö H‚ì ç¤ì å=å#á å " {ã Ý áæä%å#ã ä%Ö{ ü '(' K$Ö„×„Ø ý ú " ý ùG ã [ç¤ì å
ç¤áÊÿµáÊâ ì å î$ìË ç ¤ÜÞ¡è ë$ÿµìä$âaå#ã ä$â ô}ç Ü áæÞ¡ìÿ ì}ä$â‚× ãå#ß ì å{ìä'ô}ìQê ë ìË ç ¤Üâ¤â ì}ä$â á ã äW× ã Þ~â ß #
ì ,Qò ç¤Ü†× ìâ áÊâ ìQô}܁ë%å#ì ÷Qí Ü áæâ ܁Ý%åeâ¤Þ¡Ü ô=â á¤ã ä'îì åô}ãväâ ì}ï$â ì å
î$Ü}ä%å•ç¤ì å#ê ë ì ç å•ì ç ç¤ì å ¤áÊä å#ô Þ¡áæâ#Ø
6ø F$# í¡Ø Ø {á¤ôã ìëÞ²Ö
P '*) P .41 0. . . 1 - P . P '*)* 1 / Ô O . 0 Ö ã áæä$â " " ìë á¤ç Ö ÜÞ¡á å=Ö$Û} ü ' K Q$ð~ք ü '(' ü Ö ×„Ø ý ِ٠" ý A
Ù K ä ã â ì Ú Ø

( Q
}
‚
i{ˆ _aˆ d}h ‘cs •] o¿Xh—j=l¡`‹_  ] s dM…Xh‰] _
| h¡gd ` t h ‘cs o
] g l~h _g Š t h d^_Xˆ Š ]‚g$g m%h t ] Ž
d ` s{t _Xˆ  ] t g j~]S€{mcg$gvˆC] d s _ |
€ t

€{]
j~m

=
Š `‹_  ] _ h t m  ] Š §
f  §` g ] j j‰] Š ] d :w„f[h Š `{] s{t ½ ‘cs C
] j~]¶d ] Ž € g
]%_cd q m%_g2j~m¨€{`‹j~m t h d ˆog l¡` t i{m%_•h#gvm _cd^] _‚d t ] s _r]cg €{m Š ] q l¡] ¬ {€ ˆ t h~] _ Š ]
` t h ‚`X_ q l¡m d=d ] _cd ]9d ` s{t _Xˆ  ] t grj~] z#s d s{t y7`‹_ Š `X_  h~] _ q•t m c‘ s ] j‰m
]cg Š h~] _ Š ] Š ` ŽEŽ ]Uj~m Ž ˆ Ž ‹` h t ]9i{ˆ _Xˆ d}h ‘cs ]„yF] dO¯9€Xj s g z ` t d ] t m h#gv`‹_ j~] s{tOŠ ` Ž …Xh _am h#gv`‹_ q m _{gÏj‰]
t gv`‹_ _Xm i{] q ]5kw] d `¨x x y t ] _  `Xh~] _cd d ` s d | h¡gd ` t h~] _ |cs{Ž m h _¨¯0gv]cg Ž ` q ]cg}d ]cg'j h Ž h d ]cg ] _ Š `X_g}d}h d s m _‚dw¯
z `‹h¡g s _ ]cg €{m Š ] q l#] ¬ €{ˆ t h‰] _ Š ]¨h _aˆ i{m j~m …aj~]—] d s _ | ` t h `‹_ q l¡m d=d ] _cd ]¨h _ q ˆ €{mcg$gvm …Xj‰]• Ëm t m q le_r_?l#]cg}d

halshs-00137198, version 1 - 17 Mar 2007

t Š ‚] g c‘ s c] gd}h‰`‹_{g 
€{mcg j‰]Tg ] s j Š ]%€{] _ q m _‚dµ¯;m =z z=t X` _cd ] W

8;: " # $ +% / % ' $+% * ,. / %
\ t `‹_{g ` q l~x ¬ _ l¡m €X€{m t mbed ‘cs l¡¯ q ] sX¬Yt ] € t #h gv]cg q m _gWj~] › ÇÇ  #›;¢{›AŸY•£{›‚y s _ q c] g q ] sX¬ €{mcg$gvm i{]cg _a]
z h i s{t m%_cd q l#m h j j~] s{t gA€{m‚g q m _g'd ` s d ]cgAj~]cg[ˆ q h }d h~`X_g  : t h#g[] _‚d t ]Ex ts j~m _—] d Ëm t m q l~_ q m _gwj=l#` t i{m _ h#g m d}h~`‹_
qcs Š ’aŠ j~]„y'\ t `‹_{g `9_a] Í ` s ]o€{mcg q ] t j~]rm Š d}h z§q m _{gFj=leh _cd t h i s ] «x j[` Š„Š s €{]o€{` s{t d m _cd s _X] z `X_ Š d}h~`‹_
]cgg ] _‚d}h~] j j~] q m _gwj~] t ` Ž m _?akw]‚g«€{m‚g$g m%i{]cg ‘cs hj~] Ž ] _‚d}h~`X_•_X]%_cd'gv]^d t ` sX ] _cd ] _F€{` g h d}h~`X_ q ];€ t `Xj~`Xi s ]
] d ŽÐª Ž ]„y q ]F€ t ˆ z m Š ]  x j ]cg}d
€{mcg—g ] Š `‹_‚d ] _cd ] t¨q l s X_ ]ºj‰] Š
¿ s{t d ` s d y†j~]Td ] ¬ d ] q ]T\ t `X_gv`

Š ~j m%h t[‘cs leh j¡g[` =z z=t %] _cd s _X]F` s €Xj s g h~] s{t g Š j‰ˆcg q ]Ej~] Š d s{t ]F] dwh _  h d ] _‚dA¯E_a]
7
¥{¦
d s{t ]Mg s €{] t z h Š h~]%j j~r
] ` sUs _•h  ` ‘cs ]„½ yK¯Mg ` t d}h t7q ]oj~m •s ] Š ` ŽEŽTs _a] 
q `‹h¤d'h _ Š h d ] t j~]2j~] Š d ] s{t ¯T_X]T€{m‚gKg ]2€{] t q•t ] q m%_g'j‰] t ˆ Š h¤d q ]cg'h _‚d t h i s ]cg

q ] Š ` s{tK‘cs h Ž %] _Xm Š ]%_cd ¾ s m q l‰“§h … l Ž m h¡gA¯ Š ` Ž € t ]%_ q•t ]0gv`‹_¸ˆ Š | ] ŠEŠ ` ŽEŽ ] Š ] j s h q ]Tj‰mT€ t ]cg Š h~] _ Š ]„y
q ]Mj~mM_am d s{t ] Ž ` t d ] j j‰] q ]Mj~m  h#g h~`X_ € t X` € | ˆ d}h ‘cs ] ¥ +  Ëm Š ] ¯ºj~mr€ t ]cg Š h~] _ Š ]„yG\ t `‹_{g ` t m €X€{]%j j~]ºj‰m
_Xˆ Š ]cg$g h d ˆ q l s _ | ` t h ‚`‹_ q l¡m d=d ] _cd ] ‘cs hQ_a]Ì g `Xh dA€{m‚g z h i{ˆ yQ€ t ˆ q ˆ d ] t Ž h _Xˆ7® z#s d s{t g ] Ž …aj~m …aj~]Ym s €{mcg$gvˆ
Š m t^q ˆ Í ¯ Š `X_•_ s •¼7` s g;gvm  `X_g'…ah~] _¨€{] s©q ] Š | ` g ]cg;g s{t \ t `‹_{g ` Q¿{]cg[` t h iXh _a]cgAj~]Yg h d s ]%_cd ¯Ð€{m t dx ¬
Š l¡]cgdwj~] Ž X` _ q ] q ]Ej~mTd ] Š | _•h ‘cs ]E] d qcs € t ‹` i tvu g y i s h q ˆT€{m t«s _X]  h#g h‰`‹_ Ž m d | ˆ Ž m d}h Š h‰] _•_a]„yQg Š h~]%_cd}h#g}d ]
t ‘cs ]E\ t `‹_{g `Mg l¡] _O]cgd q ˆ d m Š | ˆ y ‘cs leh jµmÌg srt ] i{m tvq ] t gvm
] d^] _ q ˆ z h _• h d}h  ]Y€ t ` Ž ˆ d | ˆ„] _•_a]• x j ]cg}d Š j~m%h ;
€Xj~m _ u d ] q h z=z ˆ t ] ŽEŽ ]%_cd y _X] €{m‚g g ] Š `‹‚_ d ] _cd ] t q ]  ˆ t h d ˆ‚g g s €{] t z h Š h~] j j~]‚g ·ƒ;l¡]cgd q l#m h j j~] s{t g
j=l¡m d=d m Š | ] Ž ] _‚d[¯0j‰m  ˆ t h d ˆ ‘cs hËj~] Š m t m Š d ˆ t h#g ] •¼7` s gAj~] q ˆ Š ` sXat `‹_{g[m s g$g hËm d=d m Š | ˆ0¯Ej~mE€{` gd ˆ t h d ˆ q ]
g `X_S`{] Xs Xt ]„y;m s
Ž m _ h u t ]Yh t ‹` _ h ‘cs
Š `X_gvm Š t ˆ„]F¯T¾ s

j~]%i ~j m h#gg ˆ m sSz#s d s{t yGd ` s d7] _ t ]cg}d m _cd Š m €{m …Xj‰] q ] t ] i{m t q ] t¸Š ] d7m d=d m Š | ] Ž ] _cd q ]
¥
] n  “F]Yj s hQ_X` s g[_X] Š `‹_ _Xm h#gg `X_g ‘cs l s _a]Ìgv] s j~]Y`{] sXat ]„y«g `X_ ^£XÂ È Ç ›FÆ{ eÇ%Å~ĕœ  +BXX›
m q l‰“§h … l}‹“Ð]Ej=l¡] ¬ d t m%h d ‘cs h _a` s g[] _—]‚gd q `‹_ _Xˆ„yË`‹_¨€{] s d q ˆ qcs h t ]Ðj²l#` t h iXh _am j h d ˆ q ]Tj‰m

ø L Ø {á¤ôã ìëÞ=Ö$Ô3) + . . +¤Ö ×„ØÚ Ù Q "~Ú(' !%Ø
ø ó ç„ì åeâ„× á ê ë ܁äâ‚î$ì ô}ãvä åeâ Ü}â ìÞaê ë ì†ç ¤ìï ì}ÿQ× ç¤ì ×$Þ¡á åa× ÜÞ XÞ¡ã ä%å#ãËôã ÿQÿµì â × á ê ë ì î$ì ç¤Ü àvë ç è ܁â ìé á åeâ ã Þ#á¤ìää ì åeëÞ Þ~Þ¡Ü á å "„ç áæä$â ßÞ â
× ã Þ~â ß Üë îá åeâ á¤ç ç¤
ì "„ì åeâ%×$Þ¡ß ô}á å#߁ÿ ìäâ Þ¡ì×Þ¡á å•ìâ î$ß à ì ç ã ×$× ß× Ü}Þ ÜÞ¡Ü 4î Êäµ Û XԁÕWÖ × Ø%6ü K Qð#Ø
û $ ò}ó õ Üvå•ôÜë è é$â%Ý â¤é ì åeé Ü ç¤ç ã õ ä ì å=å•ã í â é ì ô}ãvÿËÿ ã ä à á¤ìõFã í â¤é á åc× ç¤Üä ì}
â #
ö „Ü?ãvä ì à á ì}õE× ç¤Üä ì}â ÷ ց*Õ & O . + Ø
û Ò *Õ &EÖ ×„ Ø K " ' Ø
û ñ
ò " ;é Ü}â„ç¤ì î vãvëËâ ã â Ü ì ã ë$Þ‚× ÜÞ~â á ô=ë ç¤ÜÞ ܁א×$Þ¡ã Ü ô éËâ ã Üé á åeâ ã Þ ã í Kë Ü î 03 áæÝ
" ;é Ëåeé ã ë ç¤î†ó ܁ä åeõ ìÞ ã ë$Þ ê ë ì åeâ á ã ä%å
" {ì ô}܁ë%å#ìó%õ á¤ç ç ×$Þ¡ì å#ì}Þ#à ì vãvëÞ‚õ ã Þ#î åØ
" é$éé G é ìë çæâ áÊÿµÜâ ì?܁×$× ì Ü ç â ã Üé á åeâ ã Þ#á¤Üä ÷ ց*Õ & O . + Ø

+%¦




!#" !$ % &' % ( )' *
 ¡h g h~`X_ q ]Ì\
q ]  h _X]T_a` Ž

t `X_gv`y'j~]
… t ] sX¬ ckw]

t ] Š s j c‘ s ~l h jW€ t ] _ q €{m t2t m €X€{` t 2
d ¯og ]‚g Š `‹j j u i s ]cg§] d;€ t ˆ q ˆ Š ]cgg ] s{t g ‘cs ]¨j=l¡`‹_
t ] d ] _‚d}h#g$gv] Ž ] _‚d q ]Eg `X_Y`{] sXat ]5a_ ` s gw]cg}d Š `X_•_ s €{m t j~];€{mcg$gvm i{] ‘cs h_?l#]cg}d €{mcg
t ] € t h#g q m _{g9d ` s d ]cg j‰]cgSˆ q h¤d}h~`‹_{g Yk[l¡m _Xm j ’ gv] | h¡gd ` t h ‘cs ] q ] \ t `X_gv` ]‚gd q ]  ] _ s ]·j=l¡m t i s{Ž ] _‚d
t mcgg ] Ž …Xj~m _‚dWj~]cg `‹€X€{` g m _‚d gA¯Tj²l#] Ž €Xh t ] q ]K¾ s m q l “§h … l}„¼ s j q ` s d ] ‘cs ] Š ]Eg s?Š„Š u gw® h _  `Xj~`X_cd m h t ] ;®
] ¬ €Xj h ‘cs ]Mj~m°g h d s m d}h‰`‹_ q m _g7j~m ‘cs ]%j j~]±gv]©d t ` sX ]o\ t `‹_{g `{y Š m t j~]©d ] ¬ d ]º_a` s g7j~]º€ t ˆcg ] _‚d m _cd0]cgdFj‰m
t ] d t m _g Š t h €•d}h~`X_ q l s _—] _‚d t ] d}h~]%_og h d s ˆ q m _{g s _X] Š ] j j s j~]F` ?y Š `‹_  m h _ Š s©q l | ˆ t ˆcg h~]„y h jËm d=d ] _ q j~m Ž ` t d

halshs-00137198, version 1 - 17 Mar 2007

¿XhQj=l¡`X_o`•… gv] t ]7¯0_a` sX ]„m s j=l¡m Ž ` s{t;‘cs l~h jˀ{` t d ]7¯Ej~m  ˆ t h¤d ˆ0] dA¯Yg m q h  s j i{m d}h~`X_Xy h j z m s dw_X`•d ] t[‘cs ]
g `X_ t m €X€{` t d2m s €{` sX `Xh t ]‚gd q h z=z ˆ t ] _‚d q ] Š ] j s h q ]cg2ƒA` t t h _a`† k[l | h#gd ` t h~]%_o_ l¡]cgd[€Xj s g5m d=d}h t ˆY€{m t j‰]
€{` sX `Xh t y Ž m%h#g Ž ] _Xm Š ˆ•XƒA];_ l¡]cgdµ€{mcgAg ] s j~] Ž ] _cdËj~] Í ] s €{`‹j h¤d}h ‘cs ] ‘cs h{]cgd q m _ i{] t ] sX¬ y Ž m h#g j~]Gd t m  m h j

q ]¨j=l | h#gd ` t h~]%_ºj s h~® ŽFª Ž „] y«j~` t g c‘ s ~l h j q ˆ  `Xh j~]¨j~m  ˆ t h d ˆÏ] d q ˆ €Xj~mbed2m s € s h#gg m _‚d :µ` s{t d m _‚dG\ t `X_gv`±gv]
 ` s j~m h¤d q ˆ d m Š%| ˆ„yj‰`‹h _ q ]cw
g ] _ Í ] sX¬¸q ;
] j=l | h#gd `Xh t ] ‘cs l~h j t m Š `X_cd ]•; †m Š ]2¯5j=l¡m Š„Š s g m d}h~`X_ q ] Š ’ _ h#g Ž ]„yh j gv]
q ˆ z ] _ q ] dSg ] q ˆ z h _•h¤d Š ` Ž§Ž ] `•… g ] t m d ] s{t ] d Š ` ŽEŽ ] _‚d m d ] s{t Y¾±m h#gUh jO]cgd­h Ž €{` g$g h¤…Xj~] ¯ s _
`•… g ] t m d ] s{t yrm h _g h ‘cs ] j~] € t ` sX ] g m g h d s m d}h‰`‹_ay q ] g ] Š ` s €{] tSq ] j~m t ˆ„m%j h d ˆ `•… gv] t ˆ y­gv`‹_

`•… g ] t m d}h‰`‹_O®5gv`‹_O`] sXXt ]7®Km z %m h d;g `X_ Š | ] Ž h _—] d ] _ t ] d ` {s t h jË]cg}dAm z=z ] Š d ˆE€{m t j~m t „ˆ m j h¤d ˆ0`•… gv] t  „ˆ ]„y
g h¤d s m d}h~`X_ €Xj~] h _a] Ž ] _‚d | ] t …‹] t d}h~]%•_ _X] ©kw]cg t ] ~j m d}h‰`‹_{g·_X] g m s{t %m h~] _cd q `‹_ Š ª d t ] s •_ h  ` ‘cs ] ] _cd t ]
j=l | h#g}d `‹h t ]„® t ˆ Š h dµ] dËj=l | h#g}d `‹h t ]„® ˆ  ˆ _X] Ž ] _cd

kwm z h i {s t ] q ‰l ¹Ðm q «
h \^] _a`ad=d `°] _‚d t ] d}h~]%_cd q
\^] _X`•d=d ` ]cg}drm s g$g h s ·
_ € t ˆ z m Š h~] t ´ q ]‚g ] ¬
j=læ˜G™ËšA› œ ›„•œMŸ7 #›  ¢{›9Ÿ7•£{›XFƒA` Ž§Ž ]¶€{`
q ˆ €Xj~m%h#g ] _‚dWm s {€ ` sX `‹h t ckw]cgW€ s …Xj h Š m d}h~`X_g
j~m z h _ qcs°t ` Ž m _ay ‘cs hAg ] Š j~`•d;€{m t;s _ m s
j=l | h#g}d ` t h~] _Xy{j s h~® ŽFª%Ž ]5€ t ˆcg ] _‚d ˆÐgv` s g z ` t Ž

l~h Ž €{` t d m _‚d ]cgFg h Ž h j h d s?q ]cg§m  ] Š—Š ] j j~] q ]Y\ t `‹_{g ` †¹Fm q h
d t m%h d g q l s X_ ] q ]Sg ]cg©m j j~` Š s d}h~`X_g©` sXat ] _cd—j‰] t ˆ Š h¤d q ]
s{t j=l | h¡gd ` t h~] _·h ¬ h~] _ay0j~]cg t ˆ  ˆ j‰m d}h~`X_g q ]Cg ]cgod t m  m sX¬

q l ¹Fm
d t ]Yd ]

q ‹h \^] _a`ad=d `Ïgv`‹_‚d Š ] _{g s{t ˆ ]cg y m%h _g h ‘cs #l `X_Ej=l¡m €X€ t ] _ q ¯
¬ d ] q l ¹Fm q hQ\;]%_X`•d=d ` ¥ ½ Ëƒ;l#]cg}d q `‹_ Š ~j ] q h#g Š ` s{t g q ]
] q ]Tg ` s{t Š ]cg | h#g}d ` t h ‘cs ]cg y ‘cs h{` sXat ];] d z ] t Ž ]Kj~] t ˆ Š h¤d y] _
Š `X_g}d}h d s ]oj~]cgFj h Ž h d ]cg y Ž m h#g7]%_cd t ]oj~]cg q ] sX¬ €{mcg$gvm i{]cg y s _Md ] Ž € g¨g l#]cg}dFˆ Š ` s j‰ˆ ‘cs hAm Ž ]%_Xˆ q ]Ïj‰m
q ˆ Š ` sX ] t d ] qcs €{mcg$gvˆT¯Eg m Š ] _{g s{t ] y q ]Kj~m t ˆ  ˆ j~m d}h‰`‹_E€ s …aj h ‘cs ];m s7t m%€X€{` t dWgv] Š t ] d„¹Ðm q h•\^] _X`•d=d `Y]cg}d

s _X]
m _ Š„ª

z ] ŽEŽ „] y z ` t Ž „ˆ ]°€{m t j~]­\^] _a] 82]cgg ] t h¤d¨€{` s{toŠ ` Ž € t ]%_ q•t ]°j~]°€{mcg$gvˆ9] d¸j~]cg Ž `] s{t g q ]9g ]cg
d t ]cg  3w_Md m _cd c‘ s ¡l m t Š | ˆ„`‹j‰`‹i s ]„y[] j j~] q h t h i{]oj~]cg z ` s h j j~]cg q ]ϓÐm t ® ]‚g ® \^m j~m d : s h#gÐ] j j~] q h t h i{]Ïj‰]
q ˆ Š t}’ €•d m%i{]E] d j‰m5€ s …aj h Š m d}h‰`‹_ qcs ÄX•œ$£X q ]^kw] d `Yx x y ] dwg ] | ] s{t d ]T¯;j~m Š ] _g s{t ]• j~m q h z=z ˆ t ] _ Š ] q ]
\ t `X_g `{y«g ] s j~]0j~m Š ` ŽEŽTs _•h Š m …Xh j h d ˆ q ]¨g `X_o`{] sXat ]Ìgv] Ž …Xj‰]Y] _rg ` s{z=z=t h t ´ q l s _a]E€{m t dW¹Fm q h \^] _a`ad=d `
g ] Š ‹` _‚d ] _cd ] q Y
] € s …aj h~] t j~¯¨` r\ t `‹_{g ` m _Xm j ’ gvm h d^] d q ¡l m s d t ]F€{m t d;g h†\ t `X_gv`­gv] Ž …aj~]Ym  `‹h t d t m  m h j j‰ˆ
¥X¥
g s{t j²l | #h gd `Xh t ] c‘ s
h j s hWˆ d m h d Š `X_cd ] Ž €{` t m h _X] y†¹Ðm q h†\^ ] _a`ad=d `Ïd t m  m h j j~]Ìg s{tGs _—€{mcg$gvˆ0j~`Xh _cd m%h _XyQ€Xj s g

û ø Ó?ԁÕWÖc× Ø ú Qvý 2 I ÔÕ Öc×„ØÚ K „ò6G„é ì«Þ¡ì× ã Þ~â~å†Ý Þ#ô=é Ü ì ã ç ã è á åeâ Ü îá* {ì}ä ã â â ã'õ ìÞ¡ì ÿ ÜÞ ì î %ò "$ë$×$אޡì å=å#ì î'Ý wã Þ#îìÞ²å†ã íXâ é ì

{Ü á ܁äË×$Þ¡á¤ì åeâ é ã ã î%Ø ÷

û û # ì ç¤ÜWå#ì î$ß î ë áæâXî$ì ç ¤ìä$â¤Þ¡ìâ á ìä Ü à ì ôQç¤ìQ×$Þ â¤Þ¡ì Ö ÿ Ü á å× ã ë$Þ?ê ë á•ç¤áÊâ‹å#ìë ç¤ìÿ ì}ä$âXç ¤ìï$â¤Þ¡Ü áæâXî$ã ää ß î$Ü}ä%å ç ìvå ß î$áæâ á¤ã ä%å ܁ä è ç¤Ü á å#ì å ãvë
í ޡ܁ä Ü á å#ì å=Öcá¤ç{å#ìÿQÝ ç ìwå#ìwå#áÊâ¤ë ìÞ?ä ìâ¤â ì}ÿ ìäâ{܁×$Þ å ç ÜWí áæäKî ëAÞ èvä ì«îì ܁ë ç ւç ÜWî$á å#ôã Þ¡î$Ü}ä ô}ì«ìäâ Þ¡ìWç ìvå†î$ì}ë$ï[߁â ܁ä$â{îá í í á ô}á ç¤ìÿµìä$â
ìï× ç¤á ô}ÜÝ ç¤ì$Ø

+X+

( Q
}
‚

+n

¥
]Tj~m t ˆ q m Š }d h~`X_ cq s ÄX•œ$£X ‘cs l¡] j j‰]T€ s …Xj h‰] À{{ƒG] dWˆ Š m t dQd ] Ž €{` t ]%j
q ]Ïj²l#`{] sXXt ] q l‰Ð
¹ m q h~®=\;]%_X`•d=d `y Š l¡]cgd ª d t ] q m _g2j~m¨€{` g h d}h~`X_ q l s _
` sX ] t d ]cgvyQ¯Ej~] s{t € s …Xj h Š m d}h~`X_Xy˯Ej~] s{t[Š ] _{g s{t ]•{³;h _g h g ] Š `X_gd t}s h d
s _ t ] d ` s{t q m _gwj~]5d ] Ž € gvy  ] t g s _Y€{mcgg ˆ5d ` s%Í ` s{t gW€Xj s gWj~`Xh _cd m h _—´ qcs j~] Š d ] s{t«z h Š d}h z q l ¹Ðm q h‹\^] _a`ad=d `{y
¯ s _a]Yˆ €{` ‘cs ]Eh _ q ˆ d ] t Ž h _aˆ„]„y˯Ðj²l#ˆ €{` ‘cs ] q l‰¹Ðm q h \^] _X`•d=d `{yQ] d q ]Ej~¯F¯ Š ] j j~] q ]Tkw] d `Ïx x ‹kw]Ej~] Š d ] s{t
m Š„Š ` Ž €Xj h d[m h _{g h s _X] q ˆ Ž m t Š | ]Ìg h Ž h j~m%h t ]Y¯ Š ] j j‰] q ]Ðkw] d `©x x t ] Ž `‹_‚d m _cd y«g s{t;q ]cg Ž h j j‰ˆ _Xm h t ]cg yQj‰] z h j
q ] c‘ s m d t ] Ž h j j‰]Em _gwj~m0gvˆ €{m t m _‚d q
]cg}d2h Ž €{` t d m _cd QkWh t ] Š ]cgÐ] ¬ d t m%h d g
j~] Š d ] s{t …ah~] _—€{` g}d ˆ t h~] s{t ¯Yg ]cg q ˆ Š

halshs-00137198, version 1 - 17 Mar 2007

q ]Eg m Ž ˆ Ž `Xh t ];i{ˆ _Xˆ d}h ‘cs ]•‚x j z m s d q `‹_ ŠG `Xh tWq m _{g j~]cgQd ] ¬ d ]cg q l ¹Ðm q h•\^] _X`•d=d ` s _a] Š j~ˆ q ]Kj~] Š d s{t ] qcs
t ` Ž m _?«ƒA] j j~]„® Š hw_ l¡]cgd2€{mcg2d ` s{t _X„ˆ ]  ] t gTj‰m̀ t ]‚g Š h~]%_ Š ] Š ` ŽEŽ ]—m  ] Š \ t `X_g `O´ m € t u g;kw] d `Mx x2j~]cg
|cs{Ž m h _g©] _ gv`‹_‚d € t `•d ˆ i{ˆcg Kkw] Š ’XŠ j~]¶g ]°d ` s{t _a]  ] t g—j~]Md |Xu Ž ] qcs €{mcg$gvˆ•«”—– › ™ËšA› œ › •œ ž¢{ ¡›„

m €X€{m t m$bed[m j‰` t g Š ` ŽEŽ ] s _Ìd ` Ž ]0€Xh  `•d ‘cs h t ˆ ` t i{m%_•h#gv]0j~mE€ t `•…Xj~ˆ Ž m d}h ‘cs ]Ei{ˆ _aˆ t m j~] qcs©Š ’aŠ j~]•?ƒ;l#]cg}d
d t u g¨g h iX_•h z h Š m d}h  ] Ž ] _‚d ‘cs ]Mgv`‹_°h _‚d t ` qcs?Š d}h~`X_U] dYgvm Š `‹_ Š j s g h~`‹_Ug ]π t ˆcg ] _‚d ] _cd Š ` ŽEŽ ]Ïj~]cg2d ] ¬ d ]cg
q l s _X] | h#g}d ` t h~] _•_a]„yK] dYgv`‹_‚dF¯oj~m z `Xh#gFj~m Ž h¡g ]o] _­m … ’ Ž ]O] d2j=l¡ˆ Š | ` qcsIq h#g Š ` s{t g qcs € t `•d m i{`X_•h#g}d ]
]cgg ] _‚d}h~] j~y«kw] d `{y Ž ˆ Ž `Xh t ]„y z j~ˆ m s ] dFg m sX ] {s tFq ]—j=l |‚s{Ž m _ h d ˆ•Qf^] _ qcs ]o¯rg mÏj h¤…{] t d ˆ y j²l |‚s{Ž
d t ` sX ]—¯Ì_a` sX ]„m s±Š `‹_ z=t `X_cd ˆ„]—¯Ìj²l#` s …Xj h qcs {€ m‚g$g ˆ—] d5¯Ìj=l~h _ Š ] t d}h d s?q ] q ]¨j=l#m  ] _ h t ´Qj~m z `X_
j=l | h#g}d ` t h~] _ t ] d t ` sX ]Fj~¯ s _a]0h Ž €{` t d m _ Š ] ‘cs ]Fj~mE€ t ]cg Š h~] _ Š ]F`a…aj h d ˆ t m%h d ;_¨€{] s d m j~` t g Š ` Ž
q ] € s h#gµj~m z h i s{t ] q l ¹Fm q h•\;]%_X`•d=d `yXj~m Š `Xj u t ]
s{t ¹Ðm q T
:µ`
h \^] _X`•d=d `{yÐj²l | h#gd `Xh t ]9_a]9€{]
› Ç$Ç › œ  ²Å†_X]2€{] s dw] _7] z=z ] d ‘cs ]Ðgv] z m h t ] s _a]

m _•h¤d ˆ©gv]
Š }d h~`‹_ q ]
€ t ] _ q•t ]„y

q ]Gkw] d `0x x Š `X_cd t ]Kj~]cg Ž m Xs  m h#g | h#g}d ` t h‰] _g 
s dOm  `‹h tr‘cs l s _S… s drg Š h~] _‚d}h z h ‘cs ]•Kk[l | h#g}d ` t ‰h ] _•_a] ›%£{›
 h#g h‰`‹_Fj s?Š h q ] q ]Eg `X_Ed t m  m%h j~y ] d q ]5j‰m5€{] tvŠ ] •€ d}h~`X_ c‘ s #l ] _
¥{p
m j‰m g ` Š h~ˆ d ˆ•Ïk[l#m t Š | ˆ `‹j~`XiXh~] _X] {€ ] s d ª d t ] ‘cs ] q l s _a] s d}h j h d ˆ z#s iXh d}h  ]„y Ž m%h#g  h d m%j~] M¿{c] g
q ˆ Š ` sX ] t d ]cg'_a]T€{] sX ] _cd …‹` s j~]  ] t gv] t j=l¡ˆ  `‹j s d}h‰`‹_ | h#g}d ` t h ‘cs ]„y ] j j‰]cgW_X];€{] sX ] _‚d ‘cs ];_X` s gW€ t `‹€{` g ] t
q ]cg2]%_g ]%h iX_X] Ž ] _cd gEg s{t2Š ] d=d ]¨ˆ  `‹j s d}h~`‹_? kw]Y€{m‚g$g ˆ q `Xh d q `X_ Š7ª d t ] Ž m j i t ˆEd ` s dGm s d ` t h#g ˆ7¯0€{m t j‰] t y




Š l¡]cgd ] _ Š %] j~m ‘cs leh j c] g}d s _ | ˆ t h d m%i{] ‘cs ] j=l¡`X_ q `‹h d mcgg s{Ž ] t Y¼7` s g·gv` ŽEŽ ]cg j~`Xh _ h Š h q ]cg
Š `X_g h q ˆ t m d}h‰`‹{_ g € t m i Ž m d}h ‘cs ]cg q ] Ëm t m q l~_ Š | ] t Š | m%_cd q m _{g j²l | h#gd `Xh t ] s _ gvm  `Xh t €{`Xj h d}h ‘cs ]
m €X€Xj h Š m …Xj‰]•;:µ` s{t ¹Ðm q h‹\^ ] _a`ad=d `{y{] dWg ]cg Š `‹_‚d ] Ž €{` t m h _{g yXj~]K€{mcg$gvˆKj~`Xh _cd m h _F]cgd …ah~] _Eh _ Š m €{m …aj~] q ]Gd ] j#g
] _{g ] h iX_a] Ž ] _‚d g  ÎE_ i{` s{z=z=t ] g l#]‚gd Š t ] s gvˆ ] _cd t ] q ] sX¬ ˆ%€{` ‘cs ]cg ‘cs h gv`‹_‚d q ]  ] _ s ]cg

¥
] _cd c‘ s Y
] j~]Y€{m‚g$g ˆ <  ¹Ðm q Q
h \^] _X`•d=d `M]‚gd s X_ ] Ž ` q ] t _a]„y
q ]oj~mMg Š h‰] _ Š ] | h#gd ` t h ‘cs ] Ž ` q ] t _a]„y Š ]%j j~] c‘ s ] t ˆcg s{Ž m
i{] t j~]¨€{mcg$gvˆ„y'` sUq l~h _g}d ts h t ]¨j~]¨€ t ˆcgv] _cd Ž m h#g Ž X` _cd t ] t
Š ` ŽEŽ ] _‚d2j~]cg Š | ` g ]cg7g ]ºgv`‹_‚d2] z=z ] Š d}h  ] Ž ] _cd^€{mcg$gvˆ„]cg )¥ = †kw]cg Š | ` g ]‚gT_?l#]%_±gv`‹_‚d;€{mcg2€Xj s gFg h Ž €Xj~]cg
{€ ` s{t m s d m _‚d ´ j~m  ˆ t h d ˆ q ]cg Š | ` gv]cgK€{m‚g$g ˆ ]cgK_a]Ìgv]Ðj‰m h#g$gv]E€{mcg;g h z m Š h j~] Ž ] _‚dAˆ d m …Xj h t yQ] dwj~m q h t ]E_?l#]cg}d

h _ Š ` Ž§Ž ] _g s{t m …aj~]cg[´Qj~]Y€{mcgg ˆY_?l#]cg}d2g ] s j~] Ž
] j j‰]ºmr] z=z ] Š d s o
ˆ j~m Š `‹_  ] t g h~`X_°h _Xm s i s{t m j~]
f^m _ {] y _a`‹_ €{mcgYg l#m‚g$g h iX_X] t j‰mÌd m Š | ] q ] ́s

û þ$" ì ç¤ã ä ç áæä%å#ô=Þ¡áÊאâ á¤ã ä îì%3 ÜÞ " ì å " {Ü ç Ü}â Ó ÔÕWÖ × Ø ú$ú Ø
û6E .ò G é ì Ü î ÿ áæâ â ì î$ç í ë è áÊâ á à ìݐë$â à áÊâ Ü ç ë%å#ì å•ã í„܁ޡô=é Ü ì ã ç¤ã è ÿQë åeâ é Ü à ìâ é ì áæޕîÜ ÷ Ö$Ó Ô}ÕWÖ ×„Ø ú $Q Ú Ø
û6F ò éé$é%Ö Ýë$â áÊ â åcâ é ì× Üvåeâ# Ø 3 ã ä Êâ ã ëQëä îìÞ²åeâ ܁ä î Xó â å•ã ä ç â é ì× Üvåeâ ÷ Ó Ô}ÕWÖ ×„Ø ú Ø
û L # í¡Ø Ø {á¤ôã ìëÞ²Ö$ Ô ) + . +¤Ö ×„Ø ý Ù ýQä Ø%ü Ø




!#" !$ % &' % ( )' *
€{mcgFg m%_g t #h g ‘cs
q ]cg ] _ Í ] sX¬ h q
h q ] _‚d}h d ˆcgFh _ q h 

]•'¿Xh«j²l | h#gd `Xh t ]¨_X` s g t ] _gv] h iX_a] q #l m …‹`
]%_cd}h d m h t ]cgrh Ž €{` t d m _‚d g y¨g `Xh d ‘cs ]Cvg `‹_
h qcs ] j j~]cg7` s Š `‹j j~] Š d}h  ]cg y;g `Xh d ‘cs leh jAj~]‚g

+

tvq g s{t _X`•d t ]Y€ t `X€ t ¨
] ˆ  `‹j s d}h‰`‹_ay«] j j~]Ïg ` s j u  ]
q h#g Š ` s{t go€{m t d}h Š h €{] q U
] j~m Š `X_g}d ts?Š d}h~`X_ q ]cg
t ] Ž ] d=d ]%_cdÐ] _ Š m s gv]• “Ðm _g Š ] q ] t _ h~] tFŠ m‚g y

j=l | #h g}d ` t h~] _S] ¬ €Xj~` t ]Mj~]M_X`X_X® q h d y Š ] ‘cs h^ˆ d m h d§d s y q ˆ _•h~ˆ y Ž m h#g7_ l¡] _ Š ‹` _‚d}h _ s m%h dF€{mcg Ž `Xh _g¸¯Mm iXh t
g ] Š t u d ] Ž ] _cd2ƒ;l#]‚gd q m%_g s _SX_ `X_X® ]cg €{m Š ]„y2€ t ` z `X_ q ˆ Ž ] _cdÌ] _ z ` s h~y ‘cs l ¹Ðm q h~® \^] _a`ad=d `  m z ` s h j j~] t
€{` s{t ] _ t ]‚g$g ` t d}h t;s _X] Ž ˆ Ž `‹h t ]Y€{] t qcs ]„y j~]Ïg ` sX ]%_•h t2q ]0d t m s{Ž m d}h#g Ž ]¨m _ Š ~h ] _Xy q ]Y€ t ` Í ] d g;€{m‚g$g ˆ‚g y
t ˆ  ˆ j~m d}h‰`‹_{g ‘cs hFg ] | ] s{t d ] _cd̯±j‰m Š ]%_g s{t ]•;ƒA` Ž§Ž ] _cd¸_X]°€{mcgrg `X_•i{] t h Š h‰y q ] t t h u t ]°j=l#m%€X€{m t ] _‚d ]

halshs-00137198, version 1 - 17 Mar 2007

t ˆ z ˆ t ] _ Š ];¯Kj=l | h#gd `Xh t ] y¯Kj~mK€ g ’aŠ | m _am j ’ g ]
ƒA] d=d ] Ž ` q ] t _ h d ˆ q l ¹Fm q h{\;]%_X`•d=d ` Š `X_  ~h ] _‚d …Xh~] _¸¯ s X_ ]2j~] Š d s{t ] qcsOŠ ’aŠ j~] Š ` Ž§Ž ] Ž ˆ d m € | ` t ] qcs
q ]  ] _•h t q ] j²l | h#gd `Xh t ] ` Š„Š h q ]%_cd m j~]  ¿Xh q ¡l m s d t ]‚g j~] Š d s{t ]cg g `X_cd €{` g$g h …Xj‰]cg ] d g ` s{| m h¤d m …Xj~]‚g y
j=l¡] _ Š%| m$b#_a] Ž ] _‚d  h#g h …Xj~] q l s _ j h at ] ¯ j=l¡m s d t ] ]‚gd z=t m%€X{€ m _cdÏ“Ð] j=l¡m d Ž ` g € |au t ] Ž ˆ q h~ˆ  m j~] ] d
t ] _am h#gg m _‚d ] q ]5Ÿ7•£{›‚y q ` Ž h _aˆ0€{m t j=l#m%_cd}h ‘cs h d ˆ7ˆ Š t m‚g m _‚d ]Ѐ t ˆ„® … s d}j‰ˆ t h~] _ _X]„y˯Ej~m Ž `‹_am t Š | h~]Fm … gv`‹j s ]
q Ï
] j=læ˜A™QšA› œ ›„•œ ž¡ŸY ¡›„º¢{›FŸY•£{›O] d§g m Š ‹` _ Š j s g h~`‹_ t ˆ  `Xj s d}h~`X_•_Xm%h t ]—] d q ]¨j~¯—¯Ìj=l s _•h  ] t g2h _ qcs gd t h‰] j~y
|c’ €{] t ® d ] Š | _X`Xj~`‹iXh ‘cs ]M] dF€{` gd ® Ž ` q ] t _X] q c] g q ] sX¬Sq ] t _•h~] t gYj h Xt ]cgvyG…Xh~]%_ q ]cgFh _ q h Š ]cg¨g ` s d}h~] _ _X] _‚d
Š ] d=d ]Yj‰] Š d s{t ]•)3wj j~]Y_X]Ïgvm s{t m h¤d ª d t ]¨m €X€Xj h Š m …Xj~]¨]%_o€{] t Ž m%_X] _ Š ]¨] d q m _{gGd ` s g[j~]cg q ˆ d m h j#gvyQ_•h ª d t ]0j‰m

g ] s j~]o€{` g g h …aj~]„y Ž m h#g7g ] Ž X… j~]π{] t d}h _X]%_cd ]•WÑW` s d§m
| h¡gd ` t h ‘cs „] y‹d ] Š | _a`‹j~`XiXh ‘cs ]„y?ˆ Š X` _X` Ž h ‘cs ]„y ¯ s _X]2`
d ] Ž € g ‘cs l¡m s g s{t iXh¡g$g ] Ž ] _cd q ] Ž ] _am Š ]cgS€Xj s g
Ž `X_Xm tvŠ | h~]Im … gv`‹j s ] y0` s m s q ]cg €{`ad}h¡g Ž ]Uˆ Š j~m%h t ˆ
q ]cg}d ts?Š d t h Š ]

s ‰j `‹_ i cq sIŠ ’aŠ j~]„yA`X_°mcgg h#g}d ]o¯ s _X]—€ t `‹i t c] g$g h~`‹_
sX ] t d s{t ] q c] gAgv` Š h‰ˆ d ˆcgw® j‰mG“Eh#g €{] t g h~`‹_Ю ] _ F
Ž ª Ž ]
Š ` Ž €Xj‰] ¬ ]cg ] d q l¡mcg €{] Š d Š `‹_‚d ] Ž €{` t m h _? j‰m
q ]­kw] d `Cx x y0g s?Š Š„u„q ]°j~m Ž ] _Xm Š ]­d `•d m j h d m%h t ]U] d

q ‚] g ¹F`X_X` t ˆ„]cg U
¾ m d t h~m t Š | ]„y q ] j~] s{t … s{t ]„m
k[l¡m _Xm j‰`‹iXh~]2m  ] Š j‰]cgQd `•d m j h d m t h#g Ž ‚] g qcsF h _ i•d}h u Ž ]Tg h u„Š j~];ˆ d m _cd
qcs f^m …•…ah z#sX’ m%_cd[j~]cg;€{] t g ˆ Š s d}h~`‹_{g  5_ Š ` Ž € t ] _ q m j‰` t g^j=leh Ž

s?Š t m d}h~] Ž h j h d m%h t ]
t ] _ z ` tvŠ ˆ„]K€{m t ~j mK€
€{` t d m _ Š ] q ]‚g t ˆ z ˆ

] d·d ] Š | a_ `‹j~`XiXh#gvˆ„]•
t ˆcg ] _ Š ] qcs i t ` s €{]

t ] _ Š ]‚g | #h gd ` t h ‘cs c] g
d m _ Š ] ‘cs ]Yj~]0d |Xu%Ž ] q ]0j=l | h¡gd `Xh t ] ’ € t ] _ q y Ž m%h#g q h z=z ˆ t ] ŽEŽ ] _cd y Š m t
q l | h#gd ` t h~]%_¶€ t ` z ]cgg h~`X_•_a] j2_X]9g s?Š Š„u„q ]°¯º¹Ðm q hK\^] _X`•d=d `†A³K… gv] _ Š ]
d ]T€{m t j~m2€Xj~m Š ] ‘cs ]2€ t ] _ q j‰] ›%£{› ›%Ç$Ç ›%œ  =Å q m _gwj~]cg q ] sX¬¸q ] t _ h~] t g

q m _{g Š c] g
m s?Š s _a]9m

 `‹j s{Ž c] g yW] d[j=l~h Ž {€ ` t
s d t ]±i t m _ q ] z h i s{t ]
_X`•d m …aj~]0g l¡] ¬ €Xj h ‘cs m _‚dAg m _{g q ` s
d ` Ž ]cg y{] dµm  ] Š j s hXj~m Ž ˆ Ž `‹h t ]Ki{ˆ _Xˆ d}h ‘cs ] q ]cgQf^ˆ  ˆ t ] _ q ]cg ŽFu t ]cg 





8

$

% * '1* % ' * +%K, %

%

$+







+ %

:"



+ # + %

¥ 7
¦
kwm Ž ˆ Ž X` h t ];i{ˆ _Xˆ d}h ‘cs ] q ]cgQf^ˆ  ˆ t ] _ q ]‚gQ¾ u t ]cg y Š ] d=d ]K³ s d t ]G¾±ˆ Ž X` h t ] y Ž ˆ Ž ‹` h t ] qcs¨Š ` t € gÀ
t ] Ž `‹_‚d m _cd q ]Ei{ˆ _Xˆ t m d}h~`X_—] _Yi{ˆ _aˆ t m d}h‰`‹_ay  `‹h‰]Th _cd ˆ t h~] s{t ] À + c‘ s
h ` z=z=t ] s ¨
_ m Š Š„u g q h t ] Š w
d m s gv` sX ] _•h t
û ò ãvâ¤é ì}Þcÿµìÿ ã Þ ÷ ÖÕ M#OAP Ö ×„Ø ú ü ýµìâ I?ÕWÖ ×„Ø%ü}Ù$Ù Ö â¤Þ¡Ü î ë áÊâ ìäµí ޡ܁ä Ü á åc× ÜÞ òÿ ߁ÿµã áÊÞ¡ì å#ì ô}ã ä îì ÷$Ø
þ $ ò åeé ì ôÜ}ä ç¤ã ã Ëÿ ܁ä × ç¤Ü ô}ì å•áÊäËé ìÞ‚ÿµìÿ ã Þ "„áæäQé ìÞ‚Ý ã î åcÿµìÿ ã Þ Ø 2ì ç¤ã ã+µî$ã õ ä å#ã ÿµÜä Ü à ìä$ë ì å•ã í â é ì× Üvåeâö[÷ ցÕNM OAP Ö
×„Ø ýú„Ø
þ$Ò ò " × ì Ü ì}Þ#÷vÖ I ÕWÖ ×„Ø ý)!$ù(" ý !Ù Ø

½

( Q
}
‚
q c] g[m _ Š„ª d t ]‚gA€{mcg$gvˆcg y˯5d t m  ] t g s _ z h j ] ¬‹Š j s g h  ] Ž ] _cd z ˆ Ž h _•h _¸m €X€{m t
Š ’aŠ j~]F€{m t j=l~h _cd ] t Ž ˆ q h~m h t ] q ]cg t ˆ  ˆ j~m d}h~`X_g ‘cs ] 82m h s g'¹Ð] j~] _Y¾±` | h~m
q m _{g s _ Š `X_cd ] ¬ d ]º…Xh~]%_ q h z=z ˆ t ]%_cd ‘cs ]9g m  ˆ t h d m …aj~]M_Xm d s{t ]°]cgd t ˆ

+ ¥
mbed Xq u '
g j‰]cg'€ t ] Ž h u t ‚] g'€{m i{]cg qcs
Ž h _ z j h i{]Fm s§Í ] s _X]2:µm s j=?ƒ;l#]cg}d
 ˆ j~ˆF´Aj=l#m%i{`‹_ h~] q ]rj=l#ˆ%€Xh Š ]º€{m t

Š m ] d°j~mCd t m _{g Ž h#gg h~`X_ Š `X_g ˆ Š s d}h  ]‚g q ]‚g¶gv` sX ] _•h t g q ] j~m t ˆ  ˆ t ] _ q ] ŽÐu t ] z=t ] Ž ] _  5_
q ˆ Š ` sXXt ]E m j~` t g'j‰] t m €X€{` t dW€{m t d}h Š s j h~] t q ]cg t ] Ž ] _¸¯Tj~] s{t €{m‚g$g ˆ akw] s{t g t ˆ  ˆ t ]%_ q ]cg ŽFu t ]cg yi t Š ]2¯
j~m q•t `‹i s ] q ]Ìj²l#ˆ €Xh Š ] Š `‹_{g ] t ] _cd^j~]cgFg ` sX ]%_•h t g qcs €{mcg$gvˆ„yGg ]¨j~]cg;d t m%_g Ž ] d=d ] _cd q ]Ìi{ˆ%_Xˆ t m d}h~`‹_ ] _
i{ˆ _aˆ t m d}h~`X_7] d j‰]cg q h z=z#s g ] _‚dËj~` t g q ]Gd t m _{g ]cg Š `‹j j‰] Š d}h  ]cgWm Ž ]%_Xˆ„]cgµ€{m t j~m q•t `Xi s ]„y Ž ` Ž ] _cd g q l~h _‚d ] _gv]
C ]‚g$g h

Š ] d2m Š Š„u g q h t ] Š d2m sX¬ g ` sX ]%_•h t g q ]¨j~] s{t €{] s €Xj~]„yWj~]cg t ] Ž ] _ t ˆ„m z=z h t Ž ] _‚d
m t h d ˆ q Ï
] j~] s{t i t ` s €{]„y'j=l s _•h¤d ˆ z `‹_ q m Ž ] _‚d m j~]Ï_aˆ Š ]cgg m h t ]o¯Ïj~] s{t g s{t h~]„y«j‰m
…{m‚g ] q ]Tj‰] s{t« h‰]0g ` Š h~m j‰]•X³ s g ]%h _ qcs €{] s €Xj~] t ] Ž ] _Xy s _ | h#gd ` t h~]%_Y]‚gd q `X_ Š h _ s d}h j~]„yh _ Š `X_ Š ]  m …aj~]•
s ] j j~] Š `‹_ _Xm h#gg m _ Š ] qcs €{mcgg ˆ0g l#` z=z=t ]Em%j~` t gA¯E] sX¬ :µ` s{t C ]cgg h Š mTj~m Ž ˆ Ž `‹h t ] z=t ] Ž ] _Ïgv]5€ t ˆ‚g ] _‚d ]
g ` s g s _X] z ` t Ž ] z=t m Š d m%j~]„y s _X] Ž h#gv]Y] _Om … ’ Ž ] t ] Ž `X_cd m%_cd q ] t ˆ  ˆ t ] _ q ] ŽFu t ]F] _ t ˆ  ˆ t ] _ q ] ŽFu t ]

halshs-00137198, version 1 - 17 Mar 2007

Š ` E
Ž ŽTs _ h~`‹_? d t m  ] t g
j~] s{t h q ] _cd}h¤d ˆo] d2j~mºgv`‹j h q

́s g c‘ s #l m sX¬ ` t h iXh _X]‚g ` t m j‰] q ]·j=l | h#g}d `‹h t ]•0kw]·€{mcg$gvˆ d t m%_g Ž h#gI]cgd s _X] m qXq h d}h~`X_
€{] t gv`‹_ _X] j j~]cg y q ‚] g z m h¤d g;] _Om €X€{m t ] _ Š ]Fh _g h iX_•h z h~m _cd g q ]0j‰m  h~]Eh _cd}h Ž ]Fm sX¬ d t m s{Ž m d}h#g
Š `Xj j~] Š d}h z g$À n •x j†g l#` z=z=t ]Eg m _{g«j²l#ˆ j‰m …{` t m d}h~`X_F€ t `X€ t ]T¯Kj²l#ˆ Š%t h d s{t ] q ]Kj=l | h¡gd `Xh t ]„y g m _{gQd t m
t ] %Š | ] t Š%| ˆ q ] z h i s{t m d}h~`X_Y` s—q ];_Xm
t ˆ Š ] €•d m Š j~;
] j~`X_•i•d ] Ž € g'm d=d ] _ qcs À ½
Š `X_g}d}h d s ]Tj=l~›‚ʼnÆ{Ä•Ç z=t ] Ž ]%_—´‹Á¼Y] Í m

q l#] ¬ {€ ˆ t h~]%_ Š c] g
Ž ]‚g Ž m Í ] s{t g[ ] d
 m h j{] ¬ €Xj h Š h¤d ];] d

t t m d}h~`X_ ‚kw]5€ t ˆ‚g ] _‚d _ l¡m q `‹_ Š {€ mcg q ] t ] Š s j g s{t j s h~y{h j_?l#]‚gd
q l s _Fh Ž €{ˆ t m d}h z y Š ] j s h q ]Ðgv]Ðgv` Xs  ] _•h t  8Tm t q ] twŠ ]Ðgv` sX ] _•h t
Ž m h¡g'€{m t q `X_•_a]
t ¼Y] Í m Ž m h#g ` s …aj h~] t ɕÀ ¥ •k[l~h ŽEŽ ˆ q h~m d ] d ˆ

€{mcgg ˆ„y j~]Y€{m t d m%i{] q ] Š ] d=d ] Ž ˆ Ž `‹h t ]Ïg hW] ¬ h i{]„m _‚d ]„y gvm
t m €X€{` t d[m s d ] Ž € g[€{m t d}h Š s j h~] t ´ j=l¡]cg €{m Š ] q l¡] ¬ €{ˆ t h~] _ Š ]
q l¡m d=d ] _cd ] q ]cg t ] Ž ]%_Xy ‘cs hK_a]±g s … g h¡gd ] qXu gYj~` t g ‘cs

‘cs K
] j‰]
 h  m _‚d

q ] Š]
z#s g h~`‹_Om  ] Š j=l~h q ] _‚d}h d ˆ q ] Š | m Š s _Ïh _ qcs h d s _
qcs €{mcgg ˆ„y d ` s dw€ s h#g$gvm _cd yË`a…aj h d u t ]Ðj²l | ` t h ‚`‹_
l#¯od t m  ] t g s _ Ž ]‚g$g h‰m _•h#g Ž ]º€ s h¡g$g m%_cd«“¸l#`

j=l~h _ Š ` Ž € t ˆ | ] _{g h~`X_ ‘cs hi{` sX ] t _Xm;j~m t ] _ Š `‹_‚d t ]5h _Xm s i s{t m%j~] q ‚] g t ] Ž ] _7] d qcs €Xj~m%_Xˆ d `Xj~`Xi s ] ’ _X]‚g y
q `X_cd§j~m  h# g h~`‹_U]‚gd7gd t h Š d ] Ž ] _‚dEh _  ] t g ]„yA€ s h#g ‘cs ] Š `X_g}d ts h d ]rm s d ` s{tFq ]Ïj~m Š%t ` ’ m _ Š ]om s € t `‹i t u g y
 h¡g h~`X_ Š `‹_{gd}h d s d}h  ]„y¨] j j‰]¶m s g$g h q l s _ Š ] t d m%h _ Ž ]cgg h~m _ h#g Ž ]•E;
ƒ l¡]cgd q l#m%h j j~] s{t g°g s{t Š ] €{`‹h _cd ‘cs ]
j=l¡m Š„Š ` t q g ] z h d yj~] Ž ]cgg h~m _ h#g Ž ]Ðg Š h~] _‚d}h z h ‘cs ]Eg ]Eg s … g}d}h d s m _‚d ¯Kj²l | ˆ t h d m i{] t ] j h iXh~] sX¬7qcs €{mcg$gvˆ„y Í}s g ‘cs l¡¯

Š ] c‘ s ±
] j²l#m t t h  ˆ ] q ] :µm s j t ˆ {u j‰]±j=l¡m Ž €Xj‰] s{toqcs Ž m j~]%_cd ] _ qcs Gkw]±€{m‚g$g ˆ z=t ] Ž ] _ ]cgdÌm  m _‚dYd ` s d
i{` sX ] t _aˆ5€{m t j~m t ] j h iXh~`X_Xy q m _{gWj~m5j‰`‹iXh ‘cs ] qcs¨t ` Ž m%_Y ] d q m _{g«j‰]cgwm j j s g h~`‹_{g ‘cs ]5j~];j~] Š d ] s{t ’ d t ` sX ]•
¹Ðˆ t h d}h~] t g q ]cg 5§m i{m …‹`‹_ q g w] _{g s _•_ h j~]cg t ] Ž ] _ g `X_cd q ˆ z h _ h#g;€{m t j~mY€{] t d ] q l s _O€{mcg$gvˆ q ˆcg h t m …Xj~]F´
q l s _X] €{m t dOj~] s{t ] ¬ h jFh _•h d}h‰m j t m €X€{] j j‰] j‰m9€{] t d ] q ]Uj=l 3 q ] _ay q l¡m s d t ]U€{m t d—h j#g©m €X€{m t d}h‰] _•_a] _cdOm sX¬

w] _{g s

_•_ h i s h q ˆcg;€{m t j~m  `Xj~`X_cd ˆ q ] t ] d t ` Xs  ] t Á%j~m  `‹h~] q ]0_a` g[€ u t c] g ɕÀXÀ{ ³;€ t u g Š ]cg Š |‚s d ]cg yQj~] s{t

þñ•Õ M#OAP Ö ×„Ø ú ü !#" ú‚ü Ú Ø
þø ò}ó ¤à ìÝ ì ìä Ü ç¤ã ä è â áÊÿµìõ Ü áæâ áæä è í ã Þ ã ë ÷vցÕNM#O P Ö × Ø ú‚ü$ü Ø
þû•Õ M#OAP Ö ×„Ø ú ü Ú Ø
þ þ +¤Ö$ìâ„Ü}Þeâ á¤ôç¤ì å 1 P ' P O ì â P O1 M O O î ë H‚ìï á ê ë ì îì ç '*) P 1 M 'µØ




!#" !$ % &' % ( )' *
| ¡h gd `Xh t ]E_ l¡]cgd ‘cs 5
] dt
‘cs ]cg}d}h~`‹_ t ]cg}d ]Y` sX ]
m s d m _‚dF¯oj~m Ž m%_•h u t ]

m s{Ž m d}h#g Ž E
] ] dWh _ ́s gd}h Š ]„y ́s
t d ] q ]Ìgvm  `Xh t g h Š ] d=d ] z ` Š
q ]Ïd t m%_g Ž ] d=d t ]oj~]o€{mcg$gvˆ

g c‘ s ¡l ¯Tj~] s{t {€ m t m q ` ¬ %m j t ] z#s i{]„y j=l¡] _ z ] tAq l~³ t t m Xh#g •kwm
m j h¡g m d}h~`X_rg s{t j‰]cg;m d t ` Š h d ˆcg2g s …Xh‰]cgK_?l#]‚gdA€{mcg qc‡ d ` s d
‘cs l#]cg}dEj‰m Ž ˆ Ž `Xh t ] ‘cs l¡¯Ïj~mÌd t m Í ] Š d `Xh t ] | h#g}d ` t h ‘cs ]

g h _•i s j h u%t ] qcs {€ ] s €Xj‰] z=t ] Ž ] _? ;_ Š `‹_{gd m d ] t m5… t h u  ] Ž ] _cd
j~m Ž ˆ Ž `‹h t ] q C
] j=l~x$g t m jr¿{] Š t ] d­]cg}d ` t i{m _•h¡g ˆ„] q l s _a] Ž
g m sX m i{]„y t h d s ]%j#g ‘cs `•d}h q h~] _{gW] dˀ{m t d m i{] Š ` ŽEŽ2s _Xm s d m h t ]K€{ˆ
8



% +% '¨Z % %;.

% %

$

halshs-00137198, version 1 - 17 Mar 2007

¼Ïl¡] _  #h g m%i{] t j‰]̀{mcgg ˆ c‘ s ¡l ¯0d t m  ] t
z h _ h t i{` sX ] t _Xˆo€{m t j s h~y q ] q ]  ] _•h t2s
t ]  h~] _‚d¨¯okw] d ` x x¨] d7¯±gvm±g `{] s{t¸q ]
] _  m | #h g$gvm _cd ]• ;_o_X]F€{] s d t ] j‰ˆ i
j=l¡m Ž m j i{m Ž ] t y m Š Š ] €•d ] tAq l ª d t ];d t
z#s d s{t ` sX ] t d„kwm Ž ˆ Ž `Xh t ]K_a]K€{]

Š` E
Ž Ž ] _cd q m _{g'j~] q ] t _•h‰]
m _ h u t ] d t u g € t ` Š | F
] ´ t
t h~` q h ‘cs ]cÀ p 

t j h at ] cq sOŠ ’aŠ j‰]
ˆ  ˆ t ] _ q ] ŽFu t ]

=: " + # + %
g s _a] Ž ˆ Ž `Xh t ]0d ` s d ]Y€ s h#g$gvm _cd ] Š #l ]cg}d[€ t ] _ q•t ]Yj~] t h#g ‘cs ] q ]
_X]om …‹` Ž h _Xm d}h‰`‹_aywd ]%j j~]ϳ;j h‰m q m _g[”W› ÇE˜A£}ÕÂX£?ʼnÇ7¢{›YŸY•£{›a x j
z ` t ŽTs j~] t¸Š j~m h t ] Ž ] _‚dFj~]cg q ˆ z h#g ‘cs ]º€{` g ]%_cd Š ] d=d ] Ž ˆ Ž `‹h t ]
1 1 % / ) %

s ] t ] d q ˆ _•h‰] t j~]F€{mcg$gvˆ ‘cs ]Fj=l#`X_—€{` t d ]7] _rg `Xh#À <XyQh j z m s dAj=l s d}h j h#gv] t y
=
m _g z ` t Ž ˆT{€ m t j s h~y Ž m h#gW_X`X_F€{` gg ˆ q ˆcÀ y{i{m t q ] t j~m;€{` gg h …ah j h d ˆ q l s _
s d ª d t ];¯;] j j‰]Tg ] s j~]Tgv` s{tvŠ ] q ]Tg m i{]‚g$g ]Tg hXj=l¡`‹_E_a]Tg m h¤d ` t q `X_•_a] t g ]cg

g ` Xs  %] _•h t Ð
g ] d§m €X€Xj h ‘cs ] t g ]‚g Š `‹_ _Xm h#gg m _
€{mcgg ˆ„y Ž m h¡gEj~] t ] Š `X_gd t}s h d y Š ] ‘cs hW_X]
Š ` Ž €•d ] t s _•h ‘cs ] Ž ] _cdwg s{t ] j j~] pX¦  5_ Š `
€ ts?q ] _‚d
j~]cg | h#gd `

+

Š ]cgÀ 7 †
 “¨l¡m s d m _‚d;€Xj s g ‘cs ]¨j~m Ž ˆ Ž `Xh t ]¨_X] t ]cg}d}h d s ]̀{m‚gTj‰]
Ž m _ ‘cs ]¨€{mcg q ¨
] €{` gv] tEŠ ] t d m h _{g2€ t `a…aj u Ž ]‚gT€{` s{t§‘cs h  ] s d
Ž € t ]%_ q m%j~` t g ‘cs ]Kj‰] › £{› › ÇÇ › œ  =Å m h¤d s _ s g m i{]G…ah~] _E€Xj s g

q 0
] g m Ž ˆ Ž X` h t ]0gv] Š `X_ q ] ‘cs ]2j~]cg t ] Ž ] _ay Ž
t h~]%_g 2³ t Š | „ˆ `‹j‰`‹i s ]cg ] doj h‰] sX¬ q ] Š `‹_{g ] t}
Š ` ŽEŽ ]Td ] j#g pQ+ -:µ` s{t d m _cdwj~]Ej~] Š d ] s{t _X]E€{] s d Ž m _ ‘cs ]
q ] Š t `Xh#g ] tºt ˆ i s j h u t ] Ž ] _‚d Š ]%j j~] q ] j=l#m Š m t h d t ]Cg `{]





m h#g Š ] d s g m%i{]0g s{z=z h dw¯§] ¬{Š j {s t „] y ] _¨m%€X€{m t ] _ Š ]„y
m d}h~`X_ g ] Ž …Xj~]%_cdOh _ s d}h j‰]cg ] d g `X_cdO€ t ` Š j~m Ž ˆcg
tKq ]Fg ] t m%€X€{] j~] t j‰m z h i s{t ] q l ¹Ðm q h\^] _X`•d=d `—] d

s{t m t Š%| h  h#gd ]„yT\^] j j‰`‹_ q m•Kkw] ›%£{›
›%Ç$Ç ›%œ  =Å
] _  h#gvm i{]Ïj~m q h¡g Š h €Xj h _X] | h#gd ` t h ‘cs ] q l s _ €{`‹h _‚d • s ]Ìd tvu gE€ t %m i Ž m d}h ‘cs ]„y'h _{gd ts{Ž ] _cd m j‰y'¯Ìj‰m Ž %m _•h u t ]
q l s _Cj~]  h~] t €{`Xj h d}h ‘cs ] p n 2ƒG] ‘cs hEj s hE€{] t Ž ] d q l¡m  `‹h tOŠ ] d=d ]°€{] t g €{] Š d}h  ]„y Š l¡]cg}d¨€ t ˆ Š h#g ˆ Ž ] c_ d q ]
€{` sX `Xh tÌs d}h j h#g ] t j~m Ž ˆ Ž `‹h t ] gv] Š `X_ q ]°€{` s{tOŠ ` Ž €{m t ] t j‰m t ˆ„m j h¤d ˆ„y^d ]%j j~] ‘cs ] Š `X_gv] t ˆ ] q m _g¨j‰]




t Š ] sX¬¸‘cs h _?l#`X_cdµ€{mcg Š ] q `‹_? Š%t h t ]Kj~] t ˆ Š h d qcs €{mcg$gvˆ„y
g ` Xs  %] _•h t y?m s¨t ˆ Š h d q X` _cd q `‹h  ] _‚d'g ] Š `X_cd ] _‚d ] w
] _ q `X_•_a] tKs _X]Yh _cd ] t € t ˆ d m d}h~`X_o€{m t d}h Š s j h u t ]„y Š l#]c}g d[j~] t ] Š t „ˆ ] t ] d^m h _{g hËh _ z j s ]%_ Š ] t g s{t j~] #z s d s{t y m%h _g h

Jþ E ò ö â¤é ìWô é ãå#ìäA× ì ã × ç¤ì õ ã ë ç¤î ä ì à ìÞ í ã Þ¡è ìâ¡Ø Qã«ÿµã Þ#ì â¤é ܁äAâ¤é ì wôã ë ç îAí ã Þ¡è á à ì$Ø4 ;ìÿµãvÞ ì×â{í Þ¡ì åeé[áÊä[îÜ á ç WÞ#áæâ¤ë Ü çXÛ õ áæâ é
× ì}Þ#á¤ã î$á¤ôì}ÿQ×$é Ü å#á å•áÊäµôã ÿQÿËë$ä Ü ç„åeé ܁ޡáÊä èå=ð ô}Ü åeâ Ü è ç ã õ áæä è é Ü ç ã ã äQõ?é ܁â%â é ì {ÜÝÝ á $ä ì}õEé ìÿËë%åeâ î$ã ÷ Ö I Õ Ö ×„Ø ú$ú Ø
Jþ F .ò G é ì ) / . .( O ô}܁ä$ä ã â Ý ìÞ¡ì ç ì è Ü}â ì î â ã â¤é ìëä ô}ã ä%å#ô}á ã ë%åØ G„é ܁â„á å•Ü îÜä è ìÞ¡ã ë%å•ô}ã ë$Þ²å#ì í ã Þ Üä ?é$ë$ÿµÜä ÷vÖ XԁÕWÖ × Ø K ' Ø
6þ Lò%öºõ ìÿQë åeâ ä ãvâ åeë$א×$Þ¡ì å=åcâ¤é ì× Ü åeâ ìä$â áÊÞ¡ì ç Ø 2ìÿËë%åeâ%ë%å#ì áæâ‰Ö ÿ Ü ì ܁ä Ü}ÿ Ü ç¤è ܁ÿ¨ã í„áæâö[÷ Ö XÔ}ÕWÖ ×„(Ø ' ý„Ø
þ I?ÕWÖ ×„Ø ù üÛ~ôã ä à ì}Þ=å#Ü}â á¤ã ä î$
ì {ìÝ ì ô}ô}Ü ìâ î ë {Ü}Ý$Ý á åeë$Þ ç¤Üÿ ß}ÿ ã áÊÞ¡ì ì}â„ç¤Ü ô}ãvä å#ìÞ¡à ܁â á¤ã ä î ëQ× Üvå=å#ß ð#Ø
E $ IµÔÕWÖ × Ø ú$4
ý ' Û~ôáæâ Ü}â á¤ã ä î ëËÿ ܁äë ì ç%î #
ë ;ìäâ Ü}â~ð#Ø
E ҕ.ò G é
ì " á åeâ ìÞ~é ã ã î†é Ü î†ä ã ä ì ì îËí ã ޕÜ}Þ#ô=é Ü ì ã ç ã è á åeâ‰å Ø #
ö P / P-O
Ô /). . . (Ô 1 P 1=ÔÔ '$ Ø ÷ Ö I?ÕWÖ ×„ Ø Q Ø
E ñ ‚äµçÊë á " ÿ ÿ ì?ç ìâ¤
é }ÿ ì îì ç Ü & , ¤#Ô O(/ 1 0/$% 1=(Ô . P, . /Qÿ ß}Þ#áæâ ìÞ¡Ü áÊâ%â ãvëâ ì{ë$ä ì?߁â ë î$ì$Ø

À

( Q
}
‚
‘cs ]Yj=l¡m =z z h t Ž 0
] kw] d `ºx x q `‹_‚dAj~m Ž ˆ Ž
Š l¡]cgd q `X_ Š g ] Š `X_ q m Ž _X] t ¯9j~] t ]
Š `X_cd t j~] t¸q l#m …{` t q j=l¡] _gv] h iX_a] Ž ] _‚d

`Xh t ]¨g ] Š X` _ q ]7]cgdG] _
 h Xt ] p•¥ y§` s q h d—m s
q ]ºj=l | h¡gd `Xh t ]„y;m h _g h

+%p
p
Š ` tE
] …Xh~] _—€Xj s g  mcg}d ]
d t ] Ž ] _‚d y  ` s j~`Xh t ‰j ] t
‘cs ]ºj=l¡m z=z h t Ž ]ºj~mr€ t ] Ž

½  x iX_a`
ˆ%€{ˆ d ] t

t ] t ~j ]F€{mcg$gvˆ
g s €X€{` g ] q ]

h u t ]rˆ €Xh i t m%€ | ] qcs
q ] t _ h~] t j h Xt ] qcs­Š ’aŠ j~] p À{ kwmY€{m t d}h Š h €{m d}h‰`‹_ q l‰¹Ðm q h \;]%_X`•d=d `ºm sX¬oz ` s h j j~]‚g q ]E“Fm t ® ]cg ®=\;m%j~m dA_?l#ˆ d m%h d
g m%_g q ` s d ] €{mcg q ˆcg h _cd ˆ t ]cg$gvˆ„]
;_
€{] s d g s{t d ` s d Š `X_g h q ˆ t ] t Š | m ‘cs ] g `{] s{t Š ` Ž§Ž ] s _a]

| h¡gd ` t h~] _ _X] pXp y;` s s _X] Š ` ŽEŽTs _Xm s d ˆ q l | h#g}d ` t h‰] _g¸m s d `{® g s{z=z h#gvm _cd ] «kw]cgo¿{`{] s{t g7_ l¡`‹_‚d q `X_ Š €{mcg
Ž m _ ‘cs ˆ q ] q ˆ  ] j~`X€X€{] t's _X] z ` t d ]Fmcg$g s{t m _ Š ] q m _gAj~] s{tKŠ m €{m Š h d ˆF¯ Š `X_•_am$bed t ]„y Š `X_g ] t ] t ] d q h t ]Tj‰]
€{mcgg ˆ•c\^] j j~`‹_ q 5
m h _ Š m t _X] Š ] d=d ];m‚g$g s{t m _ Š ] y‹j~]Kj‰] Š d ] s{t
Š ` Ž €•d ]cgv® t ] _ qcs E
q `X_cd2j~m z h~m …Xh j h d ˆ„y |
g h#gg s g qcs
p
m €X€{m t d ] _Xm _ Š ];¯Kj~m Š | t `X_•h ‘cs ] qcs¸Š | m €Xh d t ] < 


halshs-00137198, version 1 - 17 Mar 2007



m ’ m _‚dµˆ d ˆ;¯K€Xj s g h‰] s{t g t ]%€ t #h g ]‚g
m s d ] Ž ] _‚d2€ t ` Š j~m Ž „ˆ ] y']cgd Š X` _

Š X` _ =z t X` _cd ˆ;¯ q c] g
z h t Ž ˆ„Ì
] €{m t j~] s{t

8;: / ' % % : " + # + % / 1% % + & + / ' % 'ÌZ " K> %
ƒA] d=d ]0…{] j j~]¨mcg$g s{t m _ Š ]Y_ l¡]cgd Š %] €{] _ q m _‚d Ž h#g ]¨]%_Mg Š„u _X] q m _{g;j~]cg q ] sX¬rq ] t _•h~] t j h a t c] g ‘cs ]0€{` s{t
Ž h~] sX¬Ct ˆ  ˆ j‰] t gvm q ]‚gd ts?Š d}h‰`‹_?Gkw]cg > ?%œA?‚Å~  BXX› Çr¢{›rŸY•£{›Sg l¡` sXat ] _‚d¨]%_S] z=z ] d—g s{tYs a_ ] Š t h d}h ‘cs ]
t m q h Š m j~] q ] Š ]cg Š ` Ž €•d ]‚g ® t ]%_ qcs g y ] d q ]‚g | h¡gd ` t h~] _{g y €{m t j~];\;m‚g | m t Ñ«]%i (p = aΧ_X] q ] t _•h u t ] z h i s{t ] q ]

j=l | h#g}d ` t h~] _og ] Š `X_g}d ts h d m j~` t g y Ž m h#g[]%_¨_Xˆ i{m d}h z Ñ t u g[g ˆ ‹u t ]T€{` s{t j~m q h#g Š h €Xj h _X]§] j j~]T_a] Š ` t t ]cg €{`‹_ q
€{mcg t ˆ„] j j~] Ž ] _cdG¯ s _—€{] t g `X_•_am i{] qcs©t ` Ž m _Xy ¯Fj=l#] ¬{Š ] €•d}h‰`‹_ q ]cg[_X] s{z g | h#g} d ` t h~] _gA… t}‡ j~ˆcg[€{m t kw] d ` 
k[l | h#g}d ` t h‰] _—]cgdwj~]5…‹m q m s?q¨q ]Tj²l | h#gd `Xh t ]„y m d=d}h t ˆT€{m t j‰]0g m _ i—] dWj~]cg ˆ  ˆ%_X] Ž ]%_cd g'j‰]cg'€Xj s g m Š„Š h q ] _cd ] j¡g 

Š ]0d}h d t ] y j=l¡ˆ Š t h d s{t ] q ]Yj=l | h#g}d `‹h t ] q ]  h‰] _cd s _X]¨m Š d}h  h¤d ˆ q ] q h  ] t g h~`X_ c‘ s h q h#g}d t m h~]Yj=l¡m d=d ] _‚d}h~`X_ q ]cg
p 7
h _ z j s ] _ Š ]cgFg ] Š tvu d ]cg
q `Xh  ] ‚_ dA€{mcg ª d t ] t ] i{m
g s{t d ` s dµj~]cgW€ t ` Š ]cg$g s g

 kw]cgFgd ts?Š d s{t ]cg q ]̀{` Xs  X` h t y q ] t h Š%| ]cgg ]cgvyGg `X_cd
t q ˆ ]cg Š ` ŽEŽ ]Ìg ‡{t ]cg[´ ` s d t F
] j~] s{t[z=t m iXh j h¤d ˆ z m Š ]7m s
q ] q h  ] t g h~`‹_ ‘cs h g l¡` t i{m _•h#gv] _cdËd ` s dµm s j~`X_•i q ]Kj=l |

q m _{g'j~] s{t m t t X` i{m _cd ]§m €X€{m t ] _ Š ] q l¡`a… Í ]
t ˆ q h i{ˆcg y'] d q ¨
] j~] s{t j~m _•i s m%i{]„yµd ` s d ] 
s m _ q ¯Sj~m Ž h _X` t h d ˆ q l | h#gd ` t h~] _{g°ˆ

Š m Š | „ˆ ]cg yWj~]cg2³ t Š | h  ]cg2_a]
d ] Ž € g y ] j j‰]cg;]%_ t ] iXh¡gd t ] _‚d

h¡gd `Xh t ]•{¿{m _g Š ` Ž •€ d ] tW‘cs ]
Š d}h  h d ˆ < ¦ y ] j j~]cg  ˆ | h Š s j~] _‚dWj~]cg'€ t ˆ ́s i{ˆcg q ] Š ] sX¬¸‘cs {h j~]cgw`‹_‚d
h¡g h~`X_ z h i{ˆ„] q ]Yj²l s _ h  ] t g;_X]Y€{` sX m _‚d ª d t ] ‘cs l~h _Xm €X€ t `‹€ t h‰ˆ„]•
Š | m €X€{m%_cd ¯ Š ]cg € t ` Š ]cg$g s g q ] t ]cgd t h Š d}h~`X_ ] j j~]S]cg}drm‚g$g ]

t m €Xh q ] Ž ] _‚d7ˆ j h Ž h _Xˆ„]r€{m t j‰]cgY€ s h¡g$g m%_cd g < + «“Ð] t t h u t ]rj~]cg¸m €{` t h~]cg¨g ` s j~]  ˆ„]cgF€{m t ÑW] i{yGj²l | h#gd ` t h~] _

E øË ò á åeâ ã Þ¡á Ü}ä%åìï ìÞ¡ôá å#ìQè Þ¡ì ܁â‚× ãvõ ìÞ{܁ä îWå#ã ÿµì†ã í„â¤é ìÿ ä ã õ7áÊâ¡Ø G„é ì Þ#ì ô Þ¡ì ܁â ì â é ì × Ü åeâ ¡ö G„é$ë å=Ö â¤é ì Qô=é Ü}ä è ì â é ì†í¤ë$â¤ë$Þ¡ì Ü å
õ ì ç¤ç¤÷ ÖJI ÔÕ Ö ×„Ø ú ! Ú Ø
E
û I?ÕWÖ ×„Ø ú Ø
E þ.ò G é ãå#ìõ é ã õ ã ë ç î Þ#ì}× ì ܁â%â¤é ì× Ü åeâ ÿËë%åeâ ôã äâ Þ¡ã ç â¤é ì{â ì Ü ô é áÊä è†ã í é á åeâ ã Þ ÷ Ö I ÕWÖ × Ø%ü Ø
E6E ò Qå•
Ü {ì à ì}Þ#ì}ä
î ^ã â é ìÞ² Ö ã ëQõ á¤ç ç Þ¡ì ç¤ì ܁Þ~äQé á åeâ ã Þ áÊäµì Ü ô=éQä ì}õEÿ ã ÿ ì}ä$â ÷ Ö I ÕWÖ × Ø ý%Ú ü Ø
E6F ò%ö #ë îè ì î†Þ¡ì ç¤á Ü}Ý ç¤ì ܁ä î õ ã Þ~â é ã í„ìä$â¤Þ áæä$â ã â¤é ì # é$Þ¡ã ä á¤ôç¤ì å•ã í â¤é ì # é ܁×$â ìÞ ã ë%å#ì ÷vÖ$Ó ÔÕWÖ × Ø Ù Ú ìâ IµÔÕWÖ × Ø Q Ø
E L;IµÔÕWÖ × Ø Q " Ù%Ø
E IµÔÕWÖ × Ø Q " ÙËìâ × Ø Q ! ú 2 I ÕWÖ × Ø Ù„ü Ø
F $ I?ÕWÖ ×„Ø ù چ ã ç¤Ü î$á å#ô=ë%å=å#á¤ãväµìä$â¤Þ¡
ì {ìÝ ì ôô}Ü ìâ ç¤ ì {܁Ý$Ý á Þ¡ì×Þ¡ìä îËç Ü ê ë ì åeâ á¤ãvä Ø
F Ò IµÔÕWÖ × Ø ùQìâ%ׄ Ø Q !
ú " Q !AQ Ø




!#" !$ % &' % ( )' *
 h Š }d h Ž ] q ]©gvm Š s{t h~` g h d ˆ—] d q ]og m z m‚g Š h _am d}h~`X_Xy j=l |
 ˆ t h d ˆ c‘ s ~l h j q ] at m h d t ˆ  ˆ j‰] t y j=l | h#g}d ` t h‰] _¨`•…Xj h i{ˆ q l s
Ž `•d g z h i{]%_cdw] d q ˆ z ` t Ž ]%_cd y Í m h j j h ]%_ z m%h d j=l¡] ¬ h i{] _ Š ]
j~]π{m‚g$g ˆ q `‹h d ª d t ] Š `X_g}d m Ž ] _‚d t ˆ h _‚d ] t € t ˆ d ˆ—€{m t

+

h#g}d ` t h‰] _oh _{gd ts{Ž ]%_cd q ]cg;€ s h#gg m _‚d g2] d Š m %Š | m _‚dKj‰m
d}h j h#g ] tAq ]cg Ž `•d g«€{` s{tWt m Š `X_cd ] t s _F€{mcg$gvˆ ‘cs ;
] j~]cg
q ];j~m t ] Ž h#gv]T]%_ Š m s g ] q ]^d ` s d ]2m s d ` t h d ˆ5€{m‚g$g ˆF´

j~]π t ˆcg ] _‚d.< n Q
 kwm q ] t _ h u t ] z h i s{t ] q ]Ìj²l | h#gd ` t h~] _
Š `X_g}d ts h d ] €{m t j~] Š ’aŠ j~] j~] t ] _  `Xh d z h _Xm j‰] Ž ] _‚dr¯Cg `X_ |‚s{Ž m _ h d ˆ q l¡` h j§_X]¶gvm s{t m h d—€ t ˆ d ] _ q•t ]
g l¡m …?gd t m h t ]F´ z m Š ];¯Kj²l#ˆ  `‹j s d}h~`‹_§h jX_ l ’ mK€{m‚g q ]K€Xh _Xm Š j~] < ½ 
kw]±€ t ˆcg ] _‚d—] d7j~] z#s d s{t _a]M€{] sX ]%_cd¸] ¬ h¡gd ] t—‘cs ] q m _{g¨j=l¡` sX ] t d s{t ] y5j~m t ] Š `X_•_Xm%h#g$gvm _ Š ] q ]Mj‰m

halshs-00137198, version 1 - 17 Mar 2007

t ] j‰m d}h  h¤d ˆ q ­
] d ` s d ] Š | ` g ]„y2j~m±j h …{] t d ˆ„yTj~m g s{t € t h#g ] ³;€ t u g ‘cs ]Mkw] d `Cx xOm h d¨j h …{ˆ t ˆ±j~] z#s d s{tOq ]
j=l |cs{Ž m%_•h d ˆ q E
] j~mE€ t ]cg Š ~h ] _ Š ]„yQÑW] i t m €X€{] j j~] ‘cs l#`X_¨_X]Yg m s{t m h dw€{mcg'€Xj s gAm s d ` t h#gv] t j~]T€{m‚g$g ˆ§¯ q h t h i{] t
s Š ’XŠ j~]¸d m%_cd;j²l | ` t h ‚`‹_ q l¡m d=d ] _‚d ] qcsMz#s d s{t2‘cs ]Yj²l#]cg €{m Š ] q l¡] ¬ €{ˆ t h~] _ Š ] qcs
j~]¨€ t ˆcgv] _cdQ³ s d ] t Ž ] qcU
€{mcgg ˆYg `X_cd ` sX ] t dwm s j h … t ] q ]  ] _ h tAq ]cgw€ t `•d m i{`‹_ h#gd ]‚g •“ u g'j~` t g Š ] sX¬ ® Š h _X]0gv`‹_‚dW€Xj s gKgv` s{Ž h#gAm sX¬
Š `X_cd t m%h _cd ]cg q ;
] j=l | h#g}d `‹h t ] qcs̊ ’aŠ j~]„y_ h ŽÐª Ž ]2m sX¬7Š `X_cd t m%h _cd ]cg qcs
Š ` | ˆ t ] _cd ] ‘cs ] j‰] Š ’aŠ j‰] g l¡m Š |Xu  ]„y—¯¶d t m  ] t g°j=l¡m Š d}h‰`‹_ q ]¶“
q l¡` sX ] t d s{t ] ‘cs h[]cgd s _X]Mg h d s m d}h~`X_ q ]oj h …{] t d ˆ„yGj h …{] t d ˆ ‘cs h[ˆ Ž

d ] ¬ d ]• ƒ;l#]cg}d q ‹` _ Š;q ] Ž m _•h u t ]Gd t u g
s _ Š m _ x q m | `yog {s tMs _a] g h d s m d}h~`‹_
] t i{]Mg ` s gFj~]cg ’ ] sX¬Uq ] ‘cs h Š ‹` _ ‘cs ]
m s{t m%h dW]cg €{ˆ t ˆ;j~m t ˆ„] _ z ] t Ž ] twq m _{g s _ z#s d s{tWŠ `‹_‚d t m h _‚dµ` s¸q m _{g s _E€{mcgg ˆ t ˆ €{ˆ d m …Xj~] c³ s gg h~y g h•d ` s dµm s
j~`X_•i qcs̊ ’aŠ j~];j~]cg z h i s{t ]cg q l | h#g}d ` t h~] _7`‹_‚d'g s g Š h d ˆ q l¡mcg$gv] T_a` Ž … t ] s gv]cg t ˆ z j~] ¬ h~`X_gAg s{t j=l | h#g}d `‹h t ]„y ] _
m €X€{m t ] _ Š ]°ˆ%€{m t g ]‚g—] d7€{m t z `Xh#g Š `‹_‚d t m q h Š d `‹h t ]cg y;] j j~]cg Š ` Ž €{` gv] _cd z h _Xm j~] Ž ] _cd s _ Ž `•d}h z € s h¡g$g m%_cd y

́s g c‘ s ] q m _g°j‰]cg°j h Ž h d ]cg
`{] sXXt ]‚g y{] dˀXj~] h _a] Ž ] _‚d Š `

z h _am j~]cg±m €X€{` t d ˆ„]¶€{m t Ñ«]%i{y Ž `ad}h z ˆ j~m …‹` t ˆ q m _{gMj=l¡] _ Š | m$b¡_X] Ž ]%_cd q ]cg
| ˆ t ] _‚d m  ] Š j~] t ]cgd ] q ]Kj=l¡] _{g ] h iX_a] Ž ] ‚_ d q ]
t m _ йÐ] t …‹] t d

\§ f^` g$g h iX_X`Xj
D



$+

$

* "

' %

•q t c] gvy + 7 7X¦ +%u t ];ˆ q h d}h~`X_ + 7Xp y pX¦ € 
ŸY•£{›7´ ŸY•£{›‚y‚¼ «
3 kwy•kw`‹_
À
À
•
q
t
7(=
+


+
%

u
t
q
7Xp 7
+
Ÿ ´„ŸY•£{› › Ç$Ç  eÂXÆ?yX¼ 3«kwy‹kw`X_ ]cg y
]2ˆ h d}h‰`‹_ay
À
y nXnXnF€ 
q l s _E€ t ª d t ];] d q ]G\ t `X_gv`y{m … t ˆ i{ˆ«Ÿ £?Å 

•
q
t
¦ %+%u t ];ˆ q h d}h‰`‹_ay + 7 p y = ¦

ĄŸ ´
Æ{  ~¢Xœ › £7Ä=Ã;Ÿ7•£{›‚yc¼ 3Wkwyakw`X_ ]‚g y + 7 7X
< ½
•
q
t
+

7 7X
¦


%
+

u
t
q
ĄŸ ´ ĕ¢T˜A™ËšA› œ ĕœAÄ=Ã;Ÿ7•£{›‚y‚¼ 3Wkwyakw`X_ ]cg y
];ˆ h¤d}h~`‹_ay + 7(= +

Ž

m _ c‘ s 5
] j=l¡] _‚d t ] d}h~] _

€ 
y ¥ À ¥ € 
q•t ]cg y + 7 7X¦ +%u t ];ˆ q h d}h~`X_Xy + 7(=‚¥ y ¦(= € 
>YĄŸ ´ >7› œ ›‚Å~  Ç Ä=Ã5Ÿ7•£{›‚y‚¼ 3Wkwy•kw`‹_
À
•
q
t
7 7X¦ +%u t
+
q
+


>TŸ ´
ÆX š[Åe› œN>7ÄX•Ç ›'Ÿ7•£{›‚y‚¼ 3Wkwy•kw`‹_ ]cg y
];ˆ h d}h~`X_Xy 7(= À y ¥ < p € 




F ñ ò.G é ì× Üvåeâ ÿËë%åeâ%Ý ìÞ¡ì áæä$â ìÞ~×$Þ¡ìâ ì î†Ý
F ø µ
I ԁÕWÖ × Ø ù Ø

â¤é ìאÞ#ìvå#ìä$â ÷ Ö I ÕWÖ × Ø ý%Ú ý„Ø

<



Documents similaires


rossignol
les peres de leglise et la terre disrael
echecsmadiavauxversion2
compta gestion complet
noemi lefebvre mai 68 et la musique
christophe al saleh comment le vegetarien doit il reagir face aux non vegetariens


Sur le même sujet..