Abdullayev, F.; Serdyuk, A.; Shidlich, A. Widths of Functional Classes Defined by Majorants of Generalized Moduli of Smoothness in the Spaces ${\mathcal S}^{p}$. Ukr. Mat. Zhurn. 2021, 73 (6), 723-737. https://doi.org/10.37863/umzh.v73i6.6432.