Approximation of differential functions and their derivatives by parabolic splines
English version (Springer): Ukrainian Mathematical Journal 35 (1983), no. 6, pp 603-611.
Citation Example: Korneichuk N. P. Approximation of differential functions and their derivatives by parabolic splines // Ukr. Mat. Zh. - 1983. - 35, № 6. - pp. 702-710.
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