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@article{IVM_1975_1_a1, author = {G. D. Velev}, title = {Approximation by trigonometric sums of {Bern\v{s}tein} type}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {9--20}, publisher = {mathdoc}, number = {1}, year = {1975}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1975_1_a1/} }
G. D. Velev. Approximation by trigonometric sums of Bern\v{s}tein type. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (1975), pp. 9-20. http://geodesic.mathdoc.fr/item/IVM_1975_1_a1/