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@article{DE_1979_15_10_a10, author = {\`E. S. Shpigelman}, title = {The existence of regular solutions of a plane quadratic system}, journal = {Differencialʹnye uravneni\^a}, pages = {1835--1839}, publisher = {mathdoc}, volume = {15}, number = {10}, year = {1979}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DE_1979_15_10_a10/} }
È. S. Shpigelman. The existence of regular solutions of a plane quadratic system. Differencialʹnye uravneniâ, Tome 15 (1979) no. 10, pp. 1835-1839. http://geodesic.mathdoc.fr/item/DE_1979_15_10_a10/