@article{PORMA_1996__53_3_47605,
     author = {De Coster, C. and Habets, P.},
     title = {A two parameters {Ambrosetti-Prodi} problem.},
     journal = {Portugaliae mathematica},
     pages = {279--303},
     publisher = {mathdoc},
     volume = {53},
     number = {3},
     year = {1996},
     zbl = {0858.35097},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PORMA_1996__53_3_47605/}
}