@article{DE_1982_18_5_a25,
     author = {O. A. Ivanov},
     title = {Existence of periodic solutions of quasihomogeneous systems},
     journal = {Differencialʹnye uravneni\^a},
     pages = {898--901},
     publisher = {mathdoc},
     volume = {18},
     number = {5},
     year = {1982},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1982_18_5_a25/}
}