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@article{DAN_1990_313_3_a7, author = {V. V. Kovtunets}, title = {Differentiability of an operator of best uniform approximation of}, journal = {Doklady Akademii Nauk}, pages = {548--551}, publisher = {mathdoc}, volume = {313}, number = {3}, year = {1990}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1990_313_3_a7/} }
V. V. Kovtunets. Differentiability of an operator of best uniform approximation of. Doklady Akademii Nauk, Tome 313 (1990) no. 3, pp. 548-551. http://geodesic.mathdoc.fr/item/DAN_1990_313_3_a7/