ZHYHALLO, K. M.; KHARKEVYCH, Yu. I. Approximation of conjugate differentiable functions by their Abel–Poisson integrals. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 61, n. 1, p. 73–82, 2009. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3002. Acesso em: 11 apr. 2025.