@article{CMUC_1991__32_3_a10, author = {Nieto, Juan J.}, title = {Periodic solutions for third order ordinary differential equations}, journal = {Commentationes Mathematicae Universitatis Carolinae}, pages = {495--499}, publisher = {mathdoc}, volume = {32}, number = {3}, year = {1991}, mrnumber = {1159797}, zbl = {0832.34028}, language = {en}, url = {http://geodesic.mathdoc.fr/item/CMUC_1991__32_3_a10/} }