%0 Journal Article
%A Yu. V. Churin
%T Necessary and sufficient conditions for the existence of singular periodic solutions
%J Differencialʹnye uravneniâ
%D 1997
%P 714-715
%V 33
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1997_33_5_a25/
%G ru
%F DE_1997_33_5_a25