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@article{MZM_1984_36_6_a9, author = {N. N. Sorich and A. I. Stepanets}, title = {Simultaneous approximation of periodic functions and their derivatives}, journal = {Matemati\v{c}eskie zametki}, pages = {873--882}, publisher = {mathdoc}, volume = {36}, number = {6}, year = {1984}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/MZM_1984_36_6_a9/} }
N. N. Sorich; A. I. Stepanets. Simultaneous approximation of periodic functions and their derivatives. Matematičeskie zametki, Tome 36 (1984) no. 6, pp. 873-882. http://geodesic.mathdoc.fr/item/MZM_1984_36_6_a9/