%0 Journal Article %A Jolanta Przybycin %T The connection between number and form of bifurcation points and properties of the nonlinear perturbation of Berestycki type %J Annales Polonici Mathematici %D 1989 %P 129-136 %V 50 %N 2 %I mathdoc %U http://geodesic.mathdoc.fr/articles/10.4064/ap-50-2-129-136/ %R 10.4064/ap-50-2-129-136 %G en %F 10_4064_ap_50_2_129_136