@article{RSMUP_1950__19__413_0,
     author = {Colombo, Giuseppe},
     title = {Sulle oscillazioni non-lineari in due gradi di libert\`a},
     journal = {Rendiconti del Seminario Matematico della Universit\`a di Padova},
     pages = {413--441},
     publisher = {Seminario Matematico of the University of Padua},
     volume = {19},
     year = {1950},
     mrnumber = {39878},
     zbl = {0037.40001},
     language = {it},
     url = {http://archive.numdam.org/item/RSMUP_1950__19__413_0/}
}