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web.archive.org
Tuck, Christopher A. Mineral Commodity Summaries 2016(pdf). Reston, VA: U.S. Geological Survey: 90–91. 28 January 2016 [22 February 2017]. (原始内容存档(PDF)于2017-05-13).
Brininstool, Mark. Mineral Commodity Summaries – Copper(PDF). United States Geological Survey. January 2016 [28 January 2017]. (原始内容存档(PDF)于2018-12-15).
George, Micheal W. Mineral Commodity Summaries 2016(pdf). Reston, VA: U.S. Geological Survey: 152–153. 28 January 2016 [22 February 2017]. (原始内容存档(PDF)于2019-01-10).
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world-nuclear.org
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