%0 Journal Article
%A Iurie Calin
%A Stanislav Ciubotaru
%T The Lyapunov quantities and the center conditions for a~class of bidimensional polynomial systems of differential equations with nonlinearities of the fourth degree
%J Buletinul Academiei de Ştiinţe a Republicii Moldova. Matematica
%D 2017
%P 112-130
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/BASM_2017_2_a8/
%G en
%F BASM_2017_2_a8