@article{CMUC_1974__15_3_a9,
     author = {Nov\'ak, B\v{r}etislav},
     title = {Remark on periodic solutions of a linear wave equation in one dimension},
     journal = {Commentationes Mathematicae Universitatis Carolinae},
     pages = {513--519},
     publisher = {mathdoc},
     volume = {15},
     number = {3},
     year = {1974},
     mrnumber = {0355354},
     zbl = {0301.35053},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/CMUC_1974__15_3_a9/}
}