%0 Journal Article
%A I. N. Sergeev
%T The rotation method and singular numbers of three-dimensional systems
%J Differencialʹnye uravneniâ
%D 1999
%P 1630-1639
%V 35
%N 12
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1999_35_12_a5/
%G ru
%F DE_1999_35_12_a5