%0 Journal Article
%A V. V. Amel'kin
%A Ching Zan Dang
%T Strong isochronism of the center of dynamical systems with second-degree polynomials
%J Differencialʹnye uravneniâ
%D 1993
%P 739-743
%V 29
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1993_29_5_a0/
%G ru
%F DE_1993_29_5_a0