1. K. Nakanishi, “Infrared Spectra,” Nankodo, Tokyo, 1973, p. 58.
2. E. Pretsch, T. Clerc, J. Seible and W. Simon, “Tabellen zur Strukturaufklarung organischer Verbindungen mit specktroskopischen Methoden,” Japanese edition, by K. Nakanishi, M. Kojima and K. Tsutsumi, Kohdansha, Tokyo, 1985, pp. 63 and 225.
3. G. C. Levy and G. L. Nelson, “Carbon-13 Nuclear Magnetic Resonance for Organic Chemists,” Japanese edition, by S. Tanaka, K. Kanota, S. Hashimoto, H. Kitazawa, T. Nagata, J. Saito, Y. Shimizu and K. Yamaguchi, Tokyo-kagakudojin, Tokyo, 1973, p. 123.