%0 Journal Article
%A K. V. Mal'kov
%A M. M. Khapaev
%T Some methods in perturbation theory connected with averaging
%J Differencialʹnye uravneniâ
%D 1987
%P 1693-1704
%V 23
%N 10
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1987_23_10_a4/
%G ru
%F DE_1987_23_10_a4