1. Bullock, T. D., Horridge, G. A., in: Structure and Function in the nervous system of Invertebrates. II Mollusca: Gastropoda, p. 1719. San Francisco-London: Freeman and Co. 1965.
2. Kerkut, G. A., in: Invertebrate Nervous Systems, p. 1 (C. A. G. Wiersma, ed.). Chicago-London: The University of Chicago Press 1967.
3. Tauc, L., in: Physiology of the Mollusca. II, p. 387 (K. M. Wilbur and C. M. Yonge, eds.). New York: Academic Press 1966.
4. Katz, B., Miledi, R.: J. Physiol.192, 407 (1967).
5. Katz, B., Miledi, R.: ibid.207, 789 (1970).