AKBAROV U.Y.; AKBAROV S. RELATIONS BETWEEN UNDEFINED SETS AND OPERATIONS ON THEM. JournalNX - A Multidisciplinary Peer Reviewed Journal, [S. l.], v. 9, n. 12, p. 326–334, 2023. Disponível em: https://repo.journalnx.com/index.php/nx/article/view/5224. Acesso em: 8 jan. 2025.