KHARKEVYCH, Yu.I.; SHUTOVSKYI, A.M. Approximation of functions from Hӧlder class by biharmonic Poisson integrals. Carpathian Mathematical Publications, [S. l.], v. 16, n. 2, p. 631–637, 2024. DOI: 10.15330/cmp.16.2.631-637. Disponível em: https://journals.pnu.edu.ua/index.php/cmp/article/view/8243. Acesso em: 15 jan. 2025.