%0 Journal Article %A Zhidkov, P.E. %T Basis properties of eigenfunctions of nonlinear Sturm-Liouville problems %J Electronic Journal of Differential Equations %D 2000 %V 2000 %I mathdoc %U http://geodesic.mathdoc.fr/item/EJDE_2000__2000__a100/ %G en %F EJDE_2000__2000__a100