KULPESHOV, B.Sh.; SUDOPLATOV, S.V. On behaviour of 2-formulas in ordered theories with non-maximal number of countable models. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 81, n. 1, p. 68–75, 2016. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/80. Acesso em: 10 jul. 2025.