@article{PFMT_2014_1_a13,
     author = {Zhengxin Zhou},
     title = {On the periodic solutions of the rational differential equations},
     journal = {Problemy fiziki, matematiki i tehniki},
     pages = {81--84},
     publisher = {mathdoc},
     number = {1},
     year = {2014},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/PFMT_2014_1_a13/}
}