%0 Journal Article
%A A. S. Platonov
%T On the existence of a linear Pfaffian system with an arbitrary countable lower characteristic set
%J Differencialʹnye uravneniâ
%D 1999
%P 1382-1386
%V 35
%N 10
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1999_35_10_a10/
%G ru
%F DE_1999_35_10_a10