1. J.S. Lin and P. Shen, J. Non-Cryst. Solids, Part (I) (1996) in press.
2. C.E. Housecroft, in: Oxford Chemistry Primers (Oxford, 1994) p. 92.
3. W. Vogel, Chemistry of Glass, translated and edited by N. Kreidl (The American Ceramic Society, Columbus, OH, 1985) and literature cited therein.
4. S. Brawer, in: Defects in Glasses, Mater. Res. Soc. Symp. Proc. Vol. 61, eds. F.L. Galeener, D.L. Griscom and M.J. Weber, (Materials Research Society, Pittsburgh, 1986) pp. 21–27.
5. M. Tomozawa, V. McGahay and J.M. Hyde, J. Non-Cryst. Solids 123 (1990) 197.