Petrov, Yu. G. The inverse basis as applied to the mean-square approximation of a function. (English. Russian original) Zbl 0974.41001 Comput. Math. Math. Phys. 39, No. 3, 517 (1999); translation from Zh. Vychisl. Mat. Mat. Fiz. 39, No. 3, 543 (1999). MSC: 41-01 Introductory exposition (textbooks, tutorial papers, etc.) pertaining to approximations and expansions PDFBibTeX XMLCite \textit{Yu. G. Petrov}, Comput. Math. Math. Phys. 39, No. 3, 517 (1999; Zbl 0974.41001); translation from Zh. Vychisl. Mat. Mat. Fiz. 39, No. 3, 543 (1999)