1. Supported in part by National Science Foundation grant DMR 86-19688 (Mctallurgy Program).
2. G.S. Collins, S.L. Shropshire and H.-J. Jang, International Conference on Diffusion in Metals and Alloys, Balatonfured, Hungary, September 1988 (Materials Science Forum, in press).
3. H.-J. Jang, Master's Thesis, Washington State University, December 1987 (unpublished).
4. G.S. Collins and R.B. Schuhmann, Phys. Rev. B34(1986)502.
5. K. Post and F. Pleiter, Hyperfine Interactions 35(1987)615.