1. S.E. Olsen, M. Tangstad, and T. Lindstad, Production of Manganese Ferroalloys (Trondheim: Tapir Academic Press, 2007).
2. The Editors of Encyclopædia Britannica, Manganese (Encyclopædia Britannica, Inc., 2020), https://www.britannica.com/science/manganese. Accessed 6 Mar 2020.
3. L. Reijnders, J. Clean. Prod. (2016). https://doi.org/10.1016/j.jclepro.2016.05.073.
4. USGS, Manganese Data Sheet—Mineral Commodity Summaries 2020 (United States Geological Survey, 2020), https://pubs.usgs.gov/periodicals/mcs2020/mcs2020-manganese.pdf. Accessed 6 Mar 2020.
5. R. Reisfeld, in Encyclopedia of Materials—Science and Technology (New York: Elsevier, 2001), p. 6472.