@article{10_21136_CMJ_1964_100626,
     author = {Vejvoda, Otto},
     title = {Periodic solutions of a linear and weakly nonlinear wave equation in one dimension, {I}},
     journal = {Czechoslovak Mathematical Journal},
     pages = {341--382},
     publisher = {mathdoc},
     volume = {14},
     number = {3},
     year = {1964},
     doi = {10.21136/CMJ.1964.100626},
     mrnumber = {0174872},
     zbl = {0178.45302},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.21136/CMJ.1964.100626/}
}