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@article{DAN_1957_112_5_a5, author = {A. I. Koshelev}, title = {On the differentiability of solutions of elliptical differential equations}, journal = {Doklady Akademii Nauk}, pages = {806--809}, publisher = {mathdoc}, volume = {112}, number = {5}, year = {1957}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1957_112_5_a5/} }
A. I. Koshelev. On the differentiability of solutions of elliptical differential equations. Doklady Akademii Nauk, Tome 112 (1957) no. 5, pp. 806-809. http://geodesic.mathdoc.fr/item/DAN_1957_112_5_a5/