1. M. Abiko and S. Ashida, “Kesshoban no Bunshiyakuri,” ed. by H. Hidaka, Kodansha Scientific, Tokyo, 1983, pp. 77–78.
2. E. Komiya, in “Rinsyo-Ketsuekigaku,” Nanzando, Tokyo, 1962, pp. 33–37.
3. M. Mino, “Vitamin-Gaku,” ed. by The Vitamin Society of Japan, Vol. I, Tokyo-Kagakudojin, Tokyo, 1980, pp. 179–183.