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@article{DE_1971_7_9_a1, author = {V. A. Bogachev}, title = {Investigation of a singular point on the plane in the case of two zero roots}, journal = {Differencialʹnye uravneni\^a}, pages = {1560--1567}, publisher = {mathdoc}, volume = {7}, number = {9}, year = {1971}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1971_7_9_a1/} }
V. A. Bogachev. Investigation of a singular point on the plane in the case of two zero roots. Differencialʹnye uravneniâ, Tome 7 (1971) no. 9, pp. 1560-1567. http://geodesic.mathdoc.fr/item/DE_1971_7_9_a1/