1. ; ; ; ; ; ; ; Paper number 982508; Society of Automotive Engineers, October 1998.
2. ; Paper number 982429; Society of Automotive Engineers, October 1998.
3. ; ; ; ; ; ; Paper number 982511; Society of Automotive Engineers, October 1998.
4. ; Denki Gakkai Hoden Kenkyukai Shiryo 1997, ED-(209-225), 39-44 (in Japanese).
5. ; ; ; ; ; ; ; ; ; ; Paper number 2000-01-2965; Society of Automotive Engineers, 2000.