@article{ARM_2005__41_2_a8,
     author = {Kub\'a\v{c}ek, Zbyn\v{e}k and Rudolf, Boris},
     title = {On the number of periodic solutions of a generalized pendulum equation},
     journal = {Archivum mathematicum},
     pages = {197--208},
     publisher = {mathdoc},
     volume = {41},
     number = {2},
     year = {2005},
     mrnumber = {2164670},
     zbl = {1117.34041},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/ARM_2005__41_2_a8/}
}