YESHKEYEV, A.R. On Jonsson varieties and quasivarieties. Bulletin of the Karaganda University. Mathematics Series, [S. l.], v. 104, n. 4, p. 151–157, 2021. DOI: 10.31489/2021m4/151-157. Disponível em: https://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/494. Acesso em: 4 sep. 2025.