MARKIN, M. V. A Gelfand-Mazur type theorem for normed algebras. Methods of Functional Analysis and Topology, [S. l.], v. 11, n. 1, p. 63–64, 2005. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/267. Acesso em: 16 dec. 2025.