1.
Stasyuk SA. Best Approximations and Kolmogorov and Trigonometric Widths of the Classes $B_{p,θ}^{Ω}$ of Periodic Functions of Many Variables. Ukr. Mat. Zhurn. [Internet]. 2004Nov.25 [cited 2024May4];56(11):1557-68. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/3865