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@article{IVM_1973_9_a2, author = {V. V. Zhuk}, title = {Certain inequalities between best approximations of periodic functions}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {18--26}, publisher = {mathdoc}, number = {9}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1973_9_a2/} }
V. V. Zhuk. Certain inequalities between best approximations of periodic functions. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 9 (1973), pp. 18-26. http://geodesic.mathdoc.fr/item/IVM_1973_9_a2/