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l r r c ( l r r r t l : I: r l c n u i t s r r c l l - . 1 . ' f r r r c . . l r , , r g , r r r r(.l 'r l l g \ L r ( ' c l l l l l ! l l l k l l r r ( ) ( - c \ l t l r (l 'n\ t r \ \ i ( ' { ) l ( ) { \ '
f r r r t r - t t r r r t ,(rIlo 1 1 1 r rt t r [ . r . ' [ ] , l t t c n l c \ 1 , l t r c l l t r t t t t ' r ' s r r r g l c - c c ltli r r t c t t , r t t , tt nl t r r r ) , t \ \ i l \ \ :
t l t l l f t \ l l t ) , l t t ' ( ' : sI t r t l li r - t rt l t t I t ,t { r , tl . lI t ( ' ( ' ( l tI t l \ l , r 11 1 1 . 1 . 1 t ! l l t ii(t)t t gr \c t t c t t r c t ) ! l n t . c i l r ) gt l l , l t
t r i c t t t l t t 'ct r t l r c c l . r . t ( . t t r t c r t\cl , l n l [ r l r , r ' 1 . , . r c r r r t ' t l t l i r c t t t t e r o t t t . t t . t i l l t t l , t t i (r )r rl l l l l l ! r ( ) l l l J ( ' e
f , r l ' ' r r c , r t e ,i .r ln, \ l i t i s ; 1 1 . 1 . 1 1 s ; 1t o[ ',' tl rt 'e . l ' I t r r r
t i t r t t , s t t e l t , t : t l t c g c t ) e r , l ( l r r rl tr t t r , i l t \ g r ' l i l L
l , t r g ct , t h c l r l t tt c r t t c r l 1 . 1 1 1 r 11 t1
l trtr1g r , 1 p l 1 1 gl 11.1 [ l u r i n t , t l * ;r u t . l t . . ' rt l r c t , r l . r t t ' , r t i r ronf s l t t ' c t . r , f
l ' l r r . t c e I r r l l r . l u lcr l r t r l ] c n l t i t \ t l t e 1 . , 1 1 ( c n l l l l g c c [ 1 . i r r . l c t r n c J [ r , r t t c r t t :l r r t l s l r . r 1 . ctsr ] r u \ e i r 1
I r r l . c c , r r r i c t lt r u t r v i t l r t I r e u \ ( . ( ) t c ( ] n l [ ) l c x ,
t i s s t r cc n g i n c c r i n g .
t l c l t . , t t c , . t r r e , l (t i v c ( r r ! , l t t t r ' t i t l t r , t i t ' t t
r Cnt\
! I t r 1 1 | 1o r l r g l t r t . l r ,s t r t h c t r r r r l e r - r r l ,ct V
n l e J i . l t i n g t l r . : i r r t c r l r c t t , r r tr r f -t l r , . rl t r [ . ' r r l r r , r
r v i t h . r t l . r r r [ . c . 1] ' ' ' g , ) t c i l ct \i l t ] l . c c ( \ n t r ( ) l l e \ l
( l , l ) . N , , 1 1 gr t t ' t l t c : c t r [ r t i r r t ) : ,* l r t . l r i l r r
REFERENCES AND NOTES
I
2
c r i t i c ; r l f i , r s o l ' r h i s t i c u t e [i lr i r r l t r g i t i rul l | 1 1 ! ' , t i t r n s , l r . r v c l ' ' c c r rl r v l i l , r l . l c t r r t l r c p , r r t .
Tlrc nricrt)rnntirrg tcclrnitltrc thcrelirre
l r r r v i t l c s i r s i n t I l g i l n . . lc ( ) l t v c r r i c r r tr r r c t l r , , . l
t ( ) c n l l l l ( ' l . r l l r c . h l r l . c , t l r s t r i l r t r t i r r r r l, i l l i l
3
4
6
698
S(llIN(][
ir
.
\'( )l_. ]('-l
.
l,) r\l'[ill-
Il
t,)
1r
l.l
r'r
l:
18
S L D i t n l r p r s e r ,C i r ' l c l f r r g N r ) w s 1 3 1 ( 1 9 9 : l )
K D Brr:wrr tbt(! 12 1 (1992)
J Folkrnan ancJA Mo:;con.r, N.tlrtre 273 3.15
(1978)
D E l n g t r e r J A M a d r r , J [ o l k r r r : r r r .l n V t l r o C t : l l
Dev Btol 23 387 (198/) D Gospod.rrowcz G
G r r : e n b u r g C R B r r c J w r t lC
l anr;erf?t,s 38 41:r5
( 19 7 8 )
D E lngbtrr Prctc N.til ArrctrJ Strr U S A 87
3 5 2 9 1 1 9 9 ( l )- - - , . , - u r t t JJ F o l k r r r a l J C e l l 8 , , : l
109 317 (1989)
K l v l O C h r t . t l ,Fl r P . t ' . l r t l C k [ i ( l r 1 1 , 1 r 1 r[1. rl 1 r l . - t t / /
Rt'.s 193 198 ( J99 1) 1,1 L Lr t,/ .l/ Pr.r.; 1'.,'1
Acacl Sr.'r L/ S A 84 136 ( lgtj /) J f f mt-.rnran
a n d D R P r t e l k a l, r t V t t r o1 3 3 1 6 ( 1 9 7 7 l
A G B e n Z e . e v . S F , ; l r r n s o n , NL [ J u c h e r S R
t t t l t c t i ( ) t tr r f i t t , .i ly i . l t r ; r lc c l l s l y t t l t r r c t r . t r r r l
t l t e o v c r : t l l t . c r l i ) r n t . t l t c c , r tl r c c i l c t t l t t t r e .
()rrcc thc st.rrrrI is fl[rricatc.l u'itlr
Irlrorolrt l t o g r r t l ' ' ' l t y ' ,i t c ; t t t t ' c t t s c t l r c p e i l t c ( l l ) ' i 1 r ! l
r()utit)cl)'. IJecutrtcthc stanrp is pliablc, it
10
l,),)-{
B Octol-rlr 1993 acceoled I 7 March I994