JAPANESE JOURNAL OF APPLIED PHYSICS PART 1-REGULAR PAPERS SHORT NOTES & REVIEW PAPERS, vol. 37, no. 12B, page. 7158 - 7160, 1998-12
MATERIALS SCIENCE AND ENGINEERING B-SOLID STATE MATERIALS FOR ADVANCED TECHNOLOGY, vol. 37, no. 1-3, page. 172 - 176, 1996-02