1. Extraction of Uranium from Sea Water
2. Kupitz, J. 16-18 April 1997. “Rationale for Thorium Introduction”. 16-18 April, Vienna, Austria: Advisory Group Meeting on Thorium Fuel Perspectives. For IAEA estimate, see
3. Bupp, I. C. and Derian, J.C. 1997.Light Water: How the Nuclear Dream Dissolved, 15–41. New York: Basic Books.