Yanchenko, S. Ya. “Approximations of Classes $B^{Ω}_{p,θ}$ of Functions of Many Variables by Entire Functions in the Space $L_q (R^d)$”. Ukrains’kyi Matematychnyi Zhurnal 62, no. 1 (January 25, 2010): 123–135. Accessed May 1, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2848.