%0 Journal Article
%A V. V. Velichenko
%T The invariance of discrete systems
%J Doklady Akademii Nauk
%D 1969
%P 503-506
%V 185
%N 3
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1969_185_3_a2/
%G ru
%F DAN_1969_185_3_a2