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Translated from Matematicheskie Zametki, Vol. 42, No. 1, pp. 21–32, July, 1987.
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Stepanets, A.I. Best approximations of infinitely differentiable functions in the space Ls . Mathematical Notes of the Academy of Sciences of the USSR 42, 522–529 (1987). https://doi.org/10.1007/BF01138720
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DOI: https://doi.org/10.1007/BF01138720