PAVLYUK, In.I.; SUDOPLATOV, S.V. Families of theories of abelian groups and their closures. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 92, n. 4, p. 72–78, 2018. DOI: 10.31489/2018m4/72-78. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/242. Acesso em: 4 jul. 2025.