@article{EJDE_2002__2002__a49,
     author = {Costa,  David G. and Guo,  Yuxia and Ramos,  Miguel},
     title = {Existence and multiplicity results for nonlinear elliptic problems in {\(\mathbb{R}^N\)} with an indefinite functional},
     journal = {Electronic journal of differential equations},
     year = {2002},
     volume = {2002},
     zbl = {1008.35014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2002__2002__a49/}
}