TYULYUBERGENEV, R.K. On computable subgroups of the group of all unitriangular matrices over a ring. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 86, n. 2, p. 74–78, 2017. DOI: 10.31489/2017m2/74-78. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/161. Acesso em: 10 jul. 2025.