%0 Journal Article %A Powers, Victoria %T Finite Spaces of Signatures %J Canadian journal of mathematics %D 1989 %P 808-829 %V 41 %N 5 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1989-037-3/ %R 10.4153/CJM-1989-037-3 %F 10_4153_CJM_1989_037_3