Serdyuk AS, Stepanyuk TA. Order Estimates for the Best Orthogonal Trigonometric Approximations of the Classes of Convolutions of Periodic Functions of Low Smoothness. Ukr. Mat. Zhurn. [Internet]. 2015 Jul. 25 [cited 2025 Dec. 6];67(7):916–936. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/2033