Radchenko, O. Y., & Yanchenko, S. Y. (2019). Approximative characteristics of the Nikol’skii – Besov classes of functions $S_{1, θ}^r B(\mathbb{R}^d)$. Ukrains’kyi Matematychnyi Zhurnal, 71(10), 1405-1421. Retrieved from https://umj.imath.kiev.ua/index.php/umj/article/view/1523