IV. (I
aP
ba'-'-'
ea^'-'
de
2 types.
ba^'~'
cà^'~'
de
I type.
FiGUKE (i)(l)(l)(ll). — s>\. — Central : \a].
aP' bP cP dP eP fc^bc d'^bd e^^be d^^cd e-'ce e^'rfe
ar
baP—
cb
de
y'=o,i 2 types,
baP'-'
cayp'-'
eb
de
ai
baP-'
cayp-'
eb
de
y~''^ 4 » p = imod3,
at
baP-'
ca-'P'-'
cb
de
at
baP-'
ca'P'-'
cb
de
y':=:i,i^ 2 types, />simod4-
at b
baP-' C
cb
de
2 types,
baP-' c
eb
de
I type.
LES GROUPES D ORDRE f"
Figure (/.s) (11). — r^i, 5>1. — Cenlral : \a,b'.
aP'
bP' cP dP d^^cd
caP'~'
caP'-'
caP'-'
cbP'~'
cbP'-
cbP'-'
a types,
I type.
2 types.
I type.
Figure (r5l)(ll). — Central : \a,b,c\
aP'
bP'
CP
dP
eP
e-' de
et
daP'~'
2 types,
I cï
daP'-'
