1. Homepage of Ministry of Health, Labor and Welfare of Japan, http:/www.mhlw.go.jp, http://www.mhlw.go.jp/english/database/db-hw/lifetb03/3.html.
2. Materials Properties Handbook: Titanium Alloys,1994
3. Metallurgy and Technology of Practical Titanium Alloys;Ouchi,1994
4. Gunawarman, M. Niinomi, K. Fukunaga, D. Eylon, S. Fujishiro, C. Ouchi, Materials Transactions 42, 7 (2001) 1339–1348.