%0 Journal Article
%A V. V. Laricheva
%T Averaging for systems with variable period
%J Doklady Akademii Nauk
%D 1971
%P 1269-1272
%V 198
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DAN_1971_198_6_a4/
%G ru
%F DAN_1971_198_6_a4