%0 Journal Article %A Fečkan, Michal %T Existence of nonzero nonnegative solutions of semilinear equations at resonance %J Commentationes Mathematicae Universitatis Carolinae %D 1998 %P 709-719 %V 39 %N 4 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMUC_1998__39_4_a6/ %G en %F CMUC_1998__39_4_a6