1. Koto, K., Morimoto, N.: Acta Cryst. B. 31, 2268 (1975)
2. Izoitko, V.M.: Technological Mineralogy and Estimation of Ore, p. 584. Publishing House Nauka, St. Petersburg, Russia (1997). in Russian
3. Klingelhöfer, G., Bernhardt, B., Foh, J., Bonnes, U., Rodionov, D., de Souza, P.A., Schröder, Ch., Gellert, R., Kane, S., Gütlich, P., Kankeleit, E.: Hyperfine Interact. 144–145, 371 (2003)
4. Pen’kov, I.N., Safin, I.A.: Int. Geol. Rev. 9, 793 (1967)
5. Bennett, D., Miljak, D., Khachan, J.: Miner. Eng. 20, 1344 (2007)