%0 Journal Article
%A M. V. Dolov
%T Differential equations $yy'=Q_4(x,y)$, having an ellipse as limit cycle
%J Differencialʹnye uravneniâ
%D 1967
%P 898-904
%V 3
%N 6
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1967_3_6_a2/
%G ru
%F DE_1967_3_6_a2