@article{EJDE_2007__2007__a24,
     author = {Caldwell,  Scott and Castro,  Alfonso and Shivaji,  Ratnasingham and Unsurangsie,  Sumalee},
     title = {Positive solutions for classes of multiparameter elliptic semipositone problems},
     journal = {Electronic journal of differential equations},
     year = {2007},
     volume = {2007},
     zbl = {1133.35035},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/EJDE_2007__2007__a24/}
}