@article{DE_2006_42_6_a12,
     author = {A. A. Grin'},
     title = {Reduction to transversality of curves in the construction of a {Dulac} function},
     journal = {Differencialʹnye uravneni\^a},
     pages = {840--843},
     year = {2006},
     volume = {42},
     number = {6},
     language = {ru},
     url = {http://geodesic.mathdoc.fr/item/DE_2006_42_6_a12/}
}