%0 Journal Article %A Mura, Roberta Botto %T Radical Classes need not have a Unique Maximal R 0-Closed Subclass %J Canadian mathematical bulletin %D 1974 %P 597-598 %V 17 %N 4 %U http://geodesic.mathdoc.fr/articles/10.4153/CMB-1974-107-7/ %R 10.4153/CMB-1974-107-7 %F 10_4153_CMB_1974_107_7