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@article{DAN_1957_112_6_a0, author = {A. V. Bitsadze}, title = {On elliptical systems of second order partial differential equations}, journal = {Doklady Akademii Nauk}, pages = {983--986}, publisher = {mathdoc}, volume = {112}, number = {6}, year = {1957}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1957_112_6_a0/} }
A. V. Bitsadze. On elliptical systems of second order partial differential equations. Doklady Akademii Nauk, Tome 112 (1957) no. 6, pp. 983-986. http://geodesic.mathdoc.fr/item/DAN_1957_112_6_a0/