%0 Journal Article
%A Cherubini, Alessandra
%A Varisco, Ada
%T On $E_k$-rings
%J Czechoslovak Mathematical Journal
%D 1988
%P 456-463
%V 38
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1988.102241/
%R 10.21136/CMJ.1988.102241
%G en
%F 10_21136_CMJ_1988_102241