@article{DE_1996_32_6_a9,
     author = {V. G. Romanovsky},
     title = {On the cyclicity of a singular point of a cubic system},
     journal = {Differencialʹnye uravneni\^a},
     pages = {784--787},
     publisher = {mathdoc},
     volume = {32},
     number = {6},
     year = {1996},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_1996_32_6_a9/}
}