Tetrahedral chains and a curious semigroup: doi:10.17398/2605-5686.34.1.99. Extracta Mathematicae, [S. l.], v. 34, n. 1, p. 99–122, 2019. Disponível em: https://revista-em.unex.es/index.php/EM/article/view/2605-5686.34.1.99.. Acesso em: 22 dec. 2024.