@article{EJDE_1997__1997__a28,
     author = {Sango,  Mamadou},
     title = {A spectral problem with an indefinite weight for an elliptic system},
     journal = {Electronic journal of differential equations},
     year = {1997},
     volume = {1997},
     zbl = {0891.35107},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_1997__1997__a28/}
}