%0 Journal Article
%A A. G. Sokolskii
%T On the stability of Hamiltonian systems in case of zero frequency
%J Differencialʹnye uravneniâ
%D 1981
%P 1509-1510
%V 17
%N 8
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1981_17_8_a21/
%G ru
%F DE_1981_17_8_a21