@article{10_2298_TAM1301049C,
     author = {Livija Cveti\'canin},
     title = {Ninety years of {Duffing's} equation},
     journal = {Theoretical and applied mechanics},
     pages = {49 },
     publisher = {mathdoc},
     volume = {40},
     number = {1},
     year = {2013},
     doi = {10.2298/TAM1301049C},
     language = {en},
     url = {http://geodesic.mathdoc.fr/articles/10.2298/TAM1301049C/}
}