1. Processing of indium: a review
2. N. Felix , in Ullmann's Encyclopedia of Industrial Chemistry, ed. F. Ullmann, WILEY-VCH, Weinheim, 2012, vol. 19, pp. 65–74
3. U. Scwarz-Schampera and P. M.Herzig, Indium: Geology, Mineralogy, and Economics, Springer Verlag, New York, 2002
4. Historical statistics for mineral and material commodities in the United States: U.S. Geological Survey Data Series 140, http://minerals.usgs.gov/ds/2005/140/
5. Report on critical raw materials for the EU, http://ec.europa.eu/growth/sectors/raw-materials/specific-interest/critical/index_en.htm