%0 Journal Article
%A Zhao, Chenglong
%A Yuan, Yanyan
%A Liu, Yansheng
%T A necessary and sufficient condition for the existence of positive solutions to singular boundary-value problems of higher order differential equations
%J Electronic Journal of Differential Equations
%D 2006
%V 2006
%I mathdoc
%U http://geodesic.mathdoc.fr/item/EJDE_2006__2006__a69/
%G en
%F EJDE_2006__2006__a69