1. W. Harder, L. Dijkhuizen and H. Veldkamp, “The Microbe 1984, Prokaryotes and Eukaryotes,” Part II, ed. by D. P. Kelly and N. G. Carr, Cambridge University Press, Cambridge, UK, 1984, pp. 51—95.
2. A. Furuya, “Microbial Production of Nucleic Acid-related Substances,” ed. by K. Ogata, S. Kinoshita, T. Tsunoda and K. Aida, Kodansha, Tokyo, and Wiley, New York, 1976, pp. 125—156.