%0 Journal Article
%A Higgins, Peter M.
%T Digraphs and the semigroup of all functions on a finite set
%J Glasgow mathematical journal
%D 1988
%P 41-57
%V 30
%N 1
%U http://geodesic.mathdoc.fr/articles/10.1017/S0017089500007011/
%R 10.1017/S0017089500007011
%F 10_1017_S0017089500007011