Kal'chuk IV, Kharkevych YI. Approximation of the classes $W^{r}_{\beta,\infty}$ by generalized Abel-Poisson integrals. Ukr. Mat. Zhurn. [Internet]. 2022 May 20 [cited 2025 Dec. 8];74(4):507-15. Available from: https://umj.imath.kiev.ua/index.php/umj/article/view/7164