%0 Journal Article
%A V. V. Filippov
%T On an investigation of ordinary differential equations ``with respect to the first approximation''
%J Differencialʹnye uravneniâ
%D 1992
%P 1351-1355
%V 28
%N 8
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1992_28_8_a7/
%G ru
%F DE_1992_28_8_a7