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2. G. Ferraris, EMU Notes in Mineralogy (1997), Vol. 1, p. 275.
3. G. Ferraris and A. Gula, Rev. Mineral. Geochem. 57, 69 (2005).
4. G. Ferraris, Z. Kristallogr. 223, 76 (2008).
5. Handbook of Minerals (Nauka, Moscow, 1992), Vol. IV, Iss. 1 [in Russian].