1. H. N. KO,J. Mater. Sci. Lett. 8 (1989) 1438.
2. Idem, ibid.5 (1986) 464.
3. Idem, ibid.6 (1987) 801.
4. Idem, ibid.6 (1987) 175.
5. Idem, in Proceedings of the MRS International Meeting on Advanced Materials, 5, Tokyo, Japan, 1988 (Materials Research Society, Pittsburgh, Pennsylvania, 1989) p. 43.