@article{CMUC_1997__38_2_a10,
     author = {O'Regan, Donal},
     title = {Landesman {Lazer} type results for first order periodic problems},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {297--308},
     publisher = {mathdoc},
     volume = {38},
     number = {2},
     year = {1997},
     mrnumber = {1455497},
     zbl = {0893.34012},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1997__38_2_a10/}
}