SAAK, E. M. On the regular approximation of the solutions of complex elliptical equations of any order. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 18, n. 6, p. 26–40, 1966. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8457. Acesso em: 7 apr. 2025.