@article{AIHPC_2009__26_1_191_0,
     author = {Gladiali, Francesca and Grossi, Massimo},
     title = {On the {Spectrum} of a {Nonlinear} {Planar} {Problem}},
     journal = {Annales de l'I.H.P. Analyse non lin\'eaire},
     pages = {191--222},
     publisher = {Elsevier},
     volume = {26},
     number = {1},
     year = {2009},
     doi = {10.1016/j.anihpc.2007.10.004},
     mrnumber = {2483819},
     zbl = {1166.35028},
     language = {en},
     url = {http://www.numdam.org/articles/10.1016/j.anihpc.2007.10.004/}
}