@article{CMJ_2004__54_2_a7,
     author = {Papageorgiou, Evgenia H. and Papageorgiou, Nikolaos S.},
     title = {Existence of solutions and of multiple solutions for nonlinear nonsmooth periodic systems},
     journal = {Czechoslovak Mathematical Journal},
     pages = {347--371},
     publisher = {mathdoc},
     volume = {54},
     number = {2},
     year = {2004},
     mrnumber = {2059256},
     zbl = {1080.34532},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMJ_2004__54_2_a7/}
}