@article{05897649, title = {Three solutions for forced Duffing-type equations with damping term.}, journal = {Boundary Value Problems [electronic only]}, volume = {2011}, year = {2011}, doi = {10.1155/2011/736093}, zbl = {1225.34029}, language = {en}, url = {http://dml.mathdoc.fr/item/05897649} }
Li, Yongkun; Zhang, Tianwei. Three solutions for forced Duffing-type equations with damping term.. Boundary Value Problems [electronic only], Tome 2011 (2011) . doi : 10.1155/2011/736093. http://gdmltest.u-ga.fr/item/05897649/