@article{EJDE_1999__1999__a71,
     author = {Qiao,  Ning and Wang,  Zhi-Qiang},
     title = {Multiplicity results for positive solutions to non-autonomous elliptic problems},
     journal = {Electronic journal of differential equations},
     year = {1999},
     volume = {1999},
     zbl = {0928.35058},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_1999__1999__a71/}
}