1. Allbutt, M., Dell, R.M., Junkison, A.R., in: The Chemistry of Extended Defects in Non-Metallic Solids, p. 124. Proc. of the Inst. for Advanced Study on the Chem. of Extended Defects in Non-Metallic Solids, Casa Blanca Inn, Scottsdale, Arizona, April 16–26, 1969. L. Eyring, M. O’Keeffe (eds.); Amsterdam-London: North Holland Publ. Comp. 1970.
2. Damien, D., Berger, R.: J. Inorg. Nucl. Chem. Suppl. 1976, 109.
3. Charvillat, J.P., Wojalowski, A., Damien, D.: Proc. 2nd Int. Conf. Electr. Struct. Actin. Wroclaw, Poland 1976, p. 469.
4. Charvillat, J.P., Damien, D., Wojakowski, A.: Rev. Chim. Mineral. 14 (1977) 178.
5. Sleight, A.W., Prewitt, C.T.: Inorg. Chem. 7 (1968) 2282.