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@article{DAN_1975_223_3_a3, author = {A. Dzhuraev}, title = {On properties of some degenerate elliptic systems of first order in the plane}, journal = {Doklady Akademii Nauk}, pages = {533--536}, publisher = {mathdoc}, volume = {223}, number = {3}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1975_223_3_a3/} }
A. Dzhuraev. On properties of some degenerate elliptic systems of first order in the plane. Doklady Akademii Nauk, Tome 223 (1975) no. 3, pp. 533-536. http://geodesic.mathdoc.fr/item/DAN_1975_223_3_a3/