KAL'CHUK, I. V.; KHARKEVYCH, Yu. I. Approximation of the classes $W^{r}_{\beta,\infty}$ by generalized Abel-Poisson integrals. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 74, n. 4, p. 507–515, 2022. DOI: 10.37863/umzh.v74i4.7164. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/7164. Acesso em: 8 dec. 2025.