Hough, R. M.; Butt, C. R. M.; Reddy, S. M.; Verrall, M. (2007). "Gold nuggets: supergene or hypogene?". Australian Journal of Earth Sciences. 54 (7): 959–964. Bibcode:2007AuJES..54..959H. doi:10.1080/08120090701488289.
Hough, R. M.; Butt, C. R. M.; Reddy, S. M.; Verrall, M. (2007). "Gold nuggets: supergene or hypogene?". Australian Journal of Earth Sciences. 54 (7): 959–964. Bibcode:2007AuJES..54..959H. doi:10.1080/08120090701488289.
Marcello M. Veiga; Stephen M. Metcalf; Randy F. Baker; Bern Klein; Gillian Davis; Andrew Bamber; Shefa Siegel. "GMP – Manual for Training Artisanal and Small-Scale Gold Miners". Global Mercury Project. United Nations Industrial Development Organization (UNIDO). Archived from the original on 4 March 2016. Retrieved 25 October 2014.
web.archive.org
Marcello M. Veiga; Stephen M. Metcalf; Randy F. Baker; Bern Klein; Gillian Davis; Andrew Bamber; Shefa Siegel. "GMP – Manual for Training Artisanal and Small-Scale Gold Miners". Global Mercury Project. United Nations Industrial Development Organization (UNIDO). Archived from the original on 4 March 2016. Retrieved 25 October 2014.