%0 Journal Article
%A V. I. Levenshtein
%T Certain properties of code systems
%J Doklady Akademii Nauk
%D 1961
%P 1274-1277
%V 140
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1961_140_6_a10/
%G ru
%F DAN_1961_140_6_a10