Approximation by Fourier sums of functions with slowly decreasing Fourier coefficients
English version (Springer): Ukrainian Mathematical Journal 38 (1986), no. 6, pp 637-644.
Citation Example: Stepanets O. I. Approximation by Fourier sums of functions with slowly decreasing Fourier coefficients // Ukr. Mat. Zh. - 1986. - 38, № 6. - pp. 755–762.
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