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@article{DE_1976_12_4_a19, author = {I. A. Konovalov}, title = {On conditions for the monocyclicity of a certain system of differential equations}, journal = {Differencialʹnye uravneni\^a}, pages = {754--757}, publisher = {mathdoc}, volume = {12}, number = {4}, year = {1976}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1976_12_4_a19/} }
I. A. Konovalov. On conditions for the monocyclicity of a certain system of differential equations. Differencialʹnye uravneniâ, Tome 12 (1976) no. 4, pp. 754-757. http://geodesic.mathdoc.fr/item/DE_1976_12_4_a19/