Shydlich, A.L. (2004) “On Saturation of Linear Summation Methods for Fourier Series in the Spaces $S_{\varphi} ^p$”, Ukrains’kyi Matematychnyi Zhurnal, 56(1), pp. 133–138. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/3736 (Accessed: 10 April 2025).