K. V. Solich, “Kolmogorov widths of the classes $B^{\Omega}_{p, \theta}$ of periodic functions of many variables in the space $L_q$”, Ukr. Mat. Zhurn., vol. 64, no. 10, pp. 1416–1425, Oct. 2012, Accessed: Dec. 06, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/2668