1. D. C. Tran, G. H. Sigel Jr andB. Bendow,J. Lightwave Technol. LT-2 (5) (October 1984).
2. S. Shibata, M. Horiguchi, K. Jinguji, S. Mitachi, T. Kanamori andT. Manabe,Electron. Lett. 17 (1981) 775.
3. M. W. Moore, P. W. France, S. F. Carter andJ. R. Williams,Mater. Sci. Forum 32?33 (1988) 457.
4. J. J. Mecholsky, J. Lau, J. D. Mackenzie, D. C. Tran andB. Bendow, in Extended Abstracts of 2nd International Symposium on Halide Glasses, Troy, New York, 1983, p. 32.
5. J. A. fnFrietas Jr, P. C. Pureza, W. I. Roberts, U. Strom andI. D. Aggarwal,Mater. Sci. Forum 32?33 (1988).