YESHKEYEV, A.R.; ULBRIKHT, O.I.; URKEN, G.A. Similarities of Jonsson spectra’s classes. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 112, n. 4, p. 130–143, 2023. DOI: 10.31489/2023m4/130-143. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/611. Acesso em: 14 oct. 2025.