1. The 6th Symposium of Japan-China Science and Technology Exchange Association at Gakushuin University in Japan;Furuya,1993
2. S.F. Yokota, H. Yamagishi and T. Abe, in: Extended Abstracts of the 36th Spring Meeting of Japan Society of Applied Physics and Related Societies, Chiba 2p-ZP-2.
3. W. Zulehner and D. Huber, Crystals 8, Czochralski-Grown Silicon, p. 28.
4. H. Furuya, M. Kida and Y. Shimanuki, private communication.