@article{CMUC_2004__45_4_a7,
     author = {Marano, Salvatore A. and Motreanu, Dumitru},
     title = {A critical point result for non-differentiable indefinite functionals},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {663--679},
     publisher = {mathdoc},
     volume = {45},
     number = {4},
     year = {2004},
     mrnumber = {2103082},
     zbl = {1107.49005},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_2004__45_4_a7/}
}