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@article{TM_1961_62_a1, author = {S. B. Stechkin}, title = {The approximation of periodic functions by {Fej\'er} sums}, journal = {Trudy Matematicheskogo Instituta imeni V.A. Steklova}, pages = {48--60}, publisher = {mathdoc}, volume = {62}, year = {1961}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/TM_1961_62_a1/} }
S. B. Stechkin. The approximation of periodic functions by Fej\'er sums. Trudy Matematicheskogo Instituta imeni V.A. Steklova, Collection of articles on linear methods of summation of Fourier series, Tome 62 (1961), pp. 48-60. http://geodesic.mathdoc.fr/item/TM_1961_62_a1/