%0 Journal Article
%A N. N. Yuberev
%T The preservation of the sign of the Green's function of a periodic boundary value problem for a second order difference equation
%J Differencialʹnye uravneniâ
%D 1968
%P 269-275
%V 4
%N 2
%I mathdoc
%U http://geodesic.mathdoc.fr/item/DE_1968_4_2_a8/
%G ru
%F DE_1968_4_2_a8