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@article{IVM_1969_3_a4, author = {F. G. Nasibov}, title = {The order of the best approximations of certain classes of functions}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {35--41}, publisher = {mathdoc}, number = {3}, year = {1969}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1969_3_a4/} }
F. G. Nasibov. The order of the best approximations of certain classes of functions. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 3 (1969), pp. 35-41. http://geodesic.mathdoc.fr/item/IVM_1969_3_a4/