GERUS, O. F. On hyperholomorphic functions of the space variable. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 63, n. 4, p. 459–465, 2011. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2731. Acesso em: 5 dec. 2025.