%0 Journal Article %A Liu, Shu %A Jia, Mei %A Tian, Yingqiang %T Existence of positive solutions for boundary-value problems with integral boundary conditions and sign changing nonlinearities %J Electronic Journal of Differential Equations %D 2010 %V 2010 %I mathdoc %U http://geodesic.mathdoc.fr/item/EJDE_2010__2010__a178/ %G en %F EJDE_2010__2010__a178