@article{03908897, title = {A note on periodic solutions of functional differential equations.}, journal = {International Journal of Mathematics and Mathematical Sciences}, volume = {8}, year = {1985}, pages = {413-415}, doi = {10.1155/S0161171285000448}, zbl = {0569.34057}, language = {en}, url = {http://dml.mathdoc.fr/item/03908897} }
Chang, S.H. A note on periodic solutions of functional differential equations.. International Journal of Mathematics and Mathematical Sciences, Tome 8 (1985) pp. 413-415. doi : 10.1155/S0161171285000448. http://gdmltest.u-ga.fr/item/03908897/