The general form of a linear functional and a criteria for a best approximation polynomial in a space with mixed integral metric
English version (Springer): Ukrainian Mathematical Journal 25 (1973), no. 1, pp 106-110.
Citation Example: Smirnov G. S. The general form of a linear functional and a criteria for a best approximation polynomial in a space with mixed integral metric // Ukr. Mat. Zh. - 1973. - 25, № 1. - pp. 134-138.
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