CHLACHULA, J. Gemstones of eastern Kazakhstan. Geologos, [S. l.], v. 26, n. 2, p. 139–162, 2020. DOI: 10.2478/logos-2020-0013. Disponível em: https://pressto.amu.edu.pl/index.php/logos/article/view/logos-2020-0013. Acesso em: 6 jun. 2023.