1.
Voitenko SP. Best $M$-Term trigonometric approximations of the classes $B^{Ω}_{p,θ}$ of periodic functions of many variables. Ukr. Mat. Zhurn. [Internet]. 2009 Sep. 25 [cited 2025 Dec. 5];61(9):1189-9. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/3091