%0 Journal Article
%A C.C. Edmunds
%T Varieties generated by semigroups of order four.
%J Semigroup forum
%D 1980
%P 67-82
%V 21
%I mathdoc
%U http://geodesic.mathdoc.fr/item/SF_1980__21_134435/
%F SF_1980__21_134435