%0 Journal Article
%A E. S. Lyapin
%T Semigroups of directed transformations of ordered sets
%J Sbornik. Mathematics
%D 1967
%P 33-39
%V 3
%N 1
%I mathdoc
%U http://geodesic.mathdoc.fr/item/SM_1967_3_1_a2/
%G en
%F SM_1967_3_1_a2