@article{JRAM_1987__380_152957,
     author = {Pavol Quittner},
     title = {Bifurcation points and eigenvalues of inequalities of reaction-diffusion type.},
     journal = {Journal f\"ur die reine und angewandte Mathematik},
     pages = {1--13},
     publisher = {mathdoc},
     volume = {380},
     year = {1987},
     zbl = {0617.35053},
     url = {http://geodesic.mathdoc.fr/item/JRAM_1987__380_152957/}
}