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@article{MZM_1970_7_6_a12, author = {N. P. Kuptsov}, title = {Direct and inverse approximation theorems in {Banach} spaces and {Fourier} transforms}, journal = {Matemati\v{c}eskie zametki}, pages = {765--778}, publisher = {mathdoc}, volume = {7}, number = {6}, year = {1970}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1970_7_6_a12/} }
N. P. Kuptsov. Direct and inverse approximation theorems in Banach spaces and Fourier transforms. Matematičeskie zametki, Tome 7 (1970) no. 6, pp. 765-778. http://geodesic.mathdoc.fr/item/MZM_1970_7_6_a12/