Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DE_1997_33_5_a18, author = {L. A. Cherkas}, title = {The {Dulac} function for polynomial autonomous systems on a plane}, journal = {Differencialʹnye uravneni\^a}, pages = {689--699}, publisher = {mathdoc}, volume = {33}, number = {5}, year = {1997}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1997_33_5_a18/} }
L. A. Cherkas. The Dulac function for polynomial autonomous systems on a plane. Differencialʹnye uravneniâ, Tome 33 (1997) no. 5, pp. 689-699. http://geodesic.mathdoc.fr/item/DE_1997_33_5_a18/