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@article{DAN_1968_181_6_a13, author = {P. A. Frolov}, title = {Connected components of real elliptic systems on the plane}, journal = {Doklady Akademii Nauk}, pages = {1350--1353}, publisher = {mathdoc}, volume = {181}, number = {6}, year = {1968}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1968_181_6_a13/} }
P. A. Frolov. Connected components of real elliptic systems on the plane. Doklady Akademii Nauk, Tome 181 (1968) no. 6, pp. 1350-1353. http://geodesic.mathdoc.fr/item/DAN_1968_181_6_a13/