REICH, Ludwig. Families of commuting formal power series, semicanonical forms and iterative roots. Annales Mathematicae Silesianae, [S. l.], v. 8, p. 189=201, 1994. Disponível em: https://journals.us.edu.pl/index.php/AMSIL/article/view/14234. Acesso em: 8 apr. 2025.