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@article{MZM_1978_24_6_a6, author = {A. A. Ligun}, title = {Some inequalities between best approximations and moduli of continuity in an $L_2$ space}, journal = {Matemati\v{c}eskie zametki}, pages = {785--792}, publisher = {mathdoc}, volume = {24}, number = {6}, year = {1978}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1978_24_6_a6/} }
A. A. Ligun. Some inequalities between best approximations and moduli of continuity in an $L_2$ space. Matematičeskie zametki, Tome 24 (1978) no. 6, pp. 785-792. http://geodesic.mathdoc.fr/item/MZM_1978_24_6_a6/