1. Papers of Technical Group on Rotating Machines, I.E.E., Japan. Vol. RM-94–59, 1994.
2. et al. 1993 National Conference of the I.E.E., Japan, No. 811.
3. Nippon Steel Co. Electrical Steel Sheets. Cat. No. SC501.
4. Japanese Industrial Standards. Nonoriented Magnetic Steel Sheet and Strip. JISC2552, 1986.
5. Japan Deep Drawing Research Group (Supervising Editor, Yoshida). Handbook of Ease or Difficulty in Press Forming. Nikkan Kogyo Shinbun, p. 443, 1987.