Yeshkeyev, A.R., A.R. Yarullina, S.M. Amanbekov, and M.T. Kassymetova. “On Robinson Spectrum of the Semantic Jonsson Quasivariety of Unars”. Bulletin of the Karaganda University. Mathematics Series 110, no. 2 (June 30, 2023): 169–178. Accessed July 10, 2025. http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/576.