Voir la notice de l'article provenant de la source Math-Net.Ru
@article{DAN_1958_121_3_a7, author = {S. A. Telyakovskii}, title = {Approximation of differentiable functions by de la {Vall\'ee} {Poussin's} sums}, journal = {Doklady Akademii Nauk}, pages = {426--429}, publisher = {mathdoc}, volume = {121}, number = {3}, year = {1958}, language = {ru}, url = {http://geodesic.mathdoc.fr/item/DAN_1958_121_3_a7/} }
S. A. Telyakovskii. Approximation of differentiable functions by de la Vall\'ee Poussin's sums. Doklady Akademii Nauk, Tome 121 (1958) no. 3, pp. 426-429. http://geodesic.mathdoc.fr/item/DAN_1958_121_3_a7/