REMPULSKA, L.; WALCZAK, Z. On modified Picard and Gauss—Weierstrass singular integrals. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 57, n. 11, p. 1577–1584, 2005. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3710. Acesso em: 6 dec. 2025.