@article{05367991, title = {Existence of solutions of periodic boundary value problems for impulsive functional Duffing equations at nonresonance case.}, journal = {Boundary Value Problems [electronic only]}, volume = {2008}, year = {2008}, doi = {10.1155/2008/937138}, zbl = {1158.34337}, language = {en}, url = {http://dml.mathdoc.fr/item/05367991} }
Liu, Xingyuan; Liu, Yuji. Existence of solutions of periodic boundary value problems for impulsive functional Duffing equations at nonresonance case.. Boundary Value Problems [electronic only], Tome 2008 (2008) . doi : 10.1155/2008/937138. http://gdmltest.u-ga.fr/item/05367991/