Iofina, T. V. (аспирант).     On the order of approximation by Riesz means in multiplicative systems in the classes E(X)[epsilon] [Текст] / T. V. Iofina // Mathematical Notes. - 2011. - Vol. 89, № 3-4. - P. 484-498, DOI 10.1134/S0001434611030205 . - ISSN 0001-4346. - ISSN 1573-8876 Рубрики: математика ДОКУМЕНТ ПРОСМОТРЕН DE VISU: НЕТ