O. Fedunyk-Yaremchuk and S. Hembars'ka, “Estimates of approximative characteristics of the classes $B^{\Omega}_{p,\theta}$ of periodic functions of several variables with given majorant of mixed moduli of continuity in the space $L_{q}$”, Carpathian Math. Publ., vol. 11, no. 2, pp. 281–295, Dec. 2019.