1. Abundance and distribution of thorium in the carbonatite stock at Iron Hill, Powderhorn District, Gunnison County, Colorado;Armbrustmacher;US Geological Survey,1980
2. Avalon Ventures (2007) Thor Lake rare metals property. Avalon Ventures, Toronto (accessed 11 April 2007). Available from URL: www.avalonventures.com/key_projects/rare_industrial/thor_lake/