We determine the exact values of Kolmogorov and linear quasiwidths for some classes of differentiable periodic functions of two variables in the Hilbert space L 2(Q).
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Translated from Ukrains’kyi Matematychnyi Zhurnal, Vol. 61, No. 6, pp. 855 – 864, June, 2009.
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Shabozov, M.S., Akobirshoev, M.O. On exact values of quasiwidths for some classes of differentiable periodic functions of two variables. Ukr Math J 61, 1013–1024 (2009). https://doi.org/10.1007/s11253-009-0251-8
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DOI: https://doi.org/10.1007/s11253-009-0251-8