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@article{DE_1984_20_5_a6, author = {D. S. Ushkho}, title = {Qualitative investigation of a system with three centers}, journal = {Differencialʹnye uravneni\^a}, pages = {797--801}, publisher = {mathdoc}, volume = {20}, number = {5}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1984_20_5_a6/} }
D. S. Ushkho. Qualitative investigation of a system with three centers. Differencialʹnye uravneniâ, Tome 20 (1984) no. 5, pp. 797-801. http://geodesic.mathdoc.fr/item/DE_1984_20_5_a6/