%0 Journal Article %A Dlab, Vlastimil %T On a Class of Perfect Rings %J Canadian journal of mathematics %D 1970 %P 822-826 %V 22 %N 4 %U http://geodesic.mathdoc.fr/articles/10.4153/CJM-1970-092-1/ %R 10.4153/CJM-1970-092-1 %F 10_4153_CJM_1970_092_1