%0 Journal Article
%A M. N. Popa
%A K. S. Sibirskii
%T Focal cyclicity of critical points of a differential system
%J Differencialʹnye uravneniâ
%D 1986
%P 1539-1545
%V 22
%N 9
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1986_22_9_a7/
%G ru
%F DE_1986_22_9_a7