1. D.D. Carr: Industrial Minerals and Rocks, 6th ed., Society of Mining, Metallurgy, and Exploration, Inc., Littleton, CO, 1994, pp. 643–60.
2. Y.F.W. Clarke: Bull. Phil. Soc., 1889, vol. 11, p. 131.
3. T.M. Beazley: J. Met., 1998, Apr. pp. 39–42.
4. T. Ishii, R. Furuichi, and Y. Kobayashi: Thermochim. Acta, 1974, vol. 9, pp. 39–53.
5. T. Ishii, R. Furuichi, Y. Kobayashi, and S. Shimada: Hokkaido Daigaku Kogakubu Kenkyu Hokoku, 1974, vol. 71, pp. 151–61.