@article{EJDE_2000__2000__a27,
     author = {Zhidkov, P.E.},
     title = {Basis properties of eigenfunctions of nonlinear {Sturm-Liouville} problems},
     journal = {Electronic Journal of Differential Equations},
     publisher = {mathdoc},
     volume = {2000},
     year = {2000},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2000__2000__a27/}
}