1. J.B. Burns, J.R. Peterson, R.G. Haire, J. Alloys Comp. (in press).
2. D. Brown, Halides of the Lanthanides and Actinides, John Wiley and Sons, New York, 1968, p. 161.
3. J. Fuger, R.G. Haire, J.R. Peterson, J. Less-Common Metals, 98 (1984) 315; and references therein.
4. Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides
5. R.P. Turcotte, R.G. Haire, in: W. Müller, R. Lindner (Eds.), Transplutonium Elements, North-Holland, Amsterdam, 1976, p. 267.