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@article{DE_2001_37_4_a6, author = {L. A. Cherkas and I. S. Shchukina}, title = {A {Special} {Dulac} {Function} for a {Quadratic} {System} on the {Plane}}, journal = {Differencialʹnye uravneni\^a}, pages = {481--487}, publisher = {mathdoc}, volume = {37}, number = {4}, year = {2001}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_2001_37_4_a6/} }
L. A. Cherkas; I. S. Shchukina. A Special Dulac Function for a Quadratic System on the Plane. Differencialʹnye uravneniâ, Tome 37 (2001) no. 4, pp. 481-487. http://geodesic.mathdoc.fr/item/DE_2001_37_4_a6/