POLYAKOV, N.; SAVELIEV, D. Generalizations of the Rudin - Keisler preorder and their model-theoretic applications. Bulletin of L.N. Gumilyov Eurasian National University. Mathematics, computer science, mechanics series, [S. l.], v. 151, n. 2, p. 6–11, 2025. DOI: 10.32523/bulmathenu.2025/2.1. Disponível em: https://bulmathmc.enu.kz/index.php/main/article/view/323. Acesso em: 6 dec. 2025.