APPEL, P. W. . Small-scale mining – hazards and opportunities in Kyrgyzstan and Mongolia. GEUS Bulletin, Copenhagen, Denmark, v. 7, p. 77–80, 2005. DOI: 10.34194/geusb.v7.4847. Disponível em: https://geusbulletin.org/index.php/geusb/article/view/4847. Acesso em: 3 oct. 2022.