Stepanets, O. I. “Rate of Convergence of a Group of Deviations on Sets of $\bar{\psi}$−integrals”. Ukrains’kyi Matematychnyi Zhurnal 51, no. 12 (December 25, 1999): 1673–1693. Accessed April 27, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/4771.