1. Iidiard, A.B. (1957) in Handbuch der Physik, Vol 20, Ed. S. Flugge, Springer-Verlage, Berlin p. 246
2. Barr, L.W. and Iidiard, A.B. (1971) in Physical Chemistry— An Advanced Treatise, Vol 10, Eds, H. Eyring, D. Henderson and W. Jost, Academic Press, New York p. 151.
3. Chadwick, A.V. and Glyde, H.R. (1975) in Rare Gas Solids, Vol 2, Eds. M.L. Klein and J.A. Venables, Academic Press, New York, Ch. 19.
4. Corish, J. and Jacobs, P.W.M. (1973) in Surface and Defect Properties of Solids, Vol 2, Eds M.W. Roberts and J.M. Thomas, The Chemical Society, London, Chapter 7.
5. Bannon, N.M., Corish, J. and Jacobs, P.W.M. (1995) Phil. Mag. A
52, 61.