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@article{IVM_1973_1_a5, author = {V. V. Zhuk}, title = {Certain sharp inequalities between best approximations}, journal = {Izvesti\^a vys\v{s}ih u\v{c}ebnyh zavedenij. Matematika}, pages = {51--56}, publisher = {mathdoc}, number = {1}, year = {1973}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/IVM_1973_1_a5/} }
V. V. Zhuk. Certain sharp inequalities between best approximations. Izvestiâ vysših učebnyh zavedenij. Matematika, no. 1 (1973), pp. 51-56. http://geodesic.mathdoc.fr/item/IVM_1973_1_a5/