%0 Journal Article
%A J.I. FRIEDMAN
%T Proper Classes as Members of Extended Sets.
%J Mathematische Annalen
%D 1969
%P 232-240
%V 183
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MAN_1969__183_161893/
%F MAN_1969__183_161893