%0 Journal Article %A Fučík, Svatopluk %A Nečas, Jindřich %A Souček, Jiří %A Souček, Vladimír %T Upper bound for the number of eigenvalues for nonlinear operators (Preliminary communication) %J Commentationes Mathematicae Universitatis Carolinae %D 1972 %P 191-195 %V 13 %N 1 %I mathdoc %U http://geodesic.mathdoc.fr/item/CMUC_1972__13_1_a16/ %G en %F CMUC_1972__13_1_a16