%0 Journal Article
%A N. V. Pyzhkova
%A A. P. Sadovskii
%T A method for solving the problem of isochronism of the center
%J Differencialʹnye uravneniâ
%D 1980
%P 1893-1895
%V 16
%N 10
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1980_16_10_a21/
%G ru
%F DE_1980_16_10_a21