%0 Journal Article
%A Shi Mingquan
%T Some Results of the π-Semigroups
%J Mathematica balkanica
%D 1991
%P 81
%V 5
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/MABA_1991_5_2_a0/
%F MABA_1991_5_2_a0