Chaichenko, S. O. “Approximations by Fourier Sums on the Sets $L^{ψ} L^{P(∙)}$”. Ukrains’kyi Matematychnyi Zhurnal 66, no. 6 (June 25, 2014): 835–846. Accessed April 14, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/2181.