Tham khảo Kōbu_gattai

  1. Why Has Japan 'Succeeded'?: Western Technology and the Japanese Ethos by Michio Morishima p.68
  2. Nussbaum, Louis-Frédéric. (2005). "Ansei no taigoku" in Japan Encyclopedia, p. 33.
  3. 1 2 Campbell, Allen; Nobel, David S (1993). Japan: An Illustrated Encyclopedia. Kodansha. tr. 904. ISBN 406205938X.