1. Bennett MVL (1967): Mechanisms of electroreception. In: Lateral Line Detectors, Cahn P ed. Bloomington: Indiana University Press, pp 313–393
2. Bishop GH (1956): Natural history of the nerve impulse. Physiol Rev 36: 376–399
3. Bremer F (1944): L’activité “spontanée” des centres nerveux. Bull Acad Roy Med Belg (Ser 6) 9: 148–173
4. Erber J, Menzel R (1977): Visual interneurons in the median protocerebrum of the bee. J Comp Physiol 121: 65–77
5. Fain GL (1981): Integration by spikeless neurones in the retina. In: Neurones Without Impulses, Roberts A, Bush BMH, eds. Cambridge: Cambridge University Press, pp 29–59