%0 Journal Article
%A A. A. Shum
%T Relative varieties of algebraic systems and propositional calculi
%J Doklady Akademii Nauk
%D 1985
%P 538-541
%V 282
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1985_282_3_a6/
%G ru
%F DAN_1985_282_3_a6