1. Aros, B. & Vigh, B. 1960. Histology of the neurohormonal apparatus in invertebrates. Acta morph. hung., 9: 13.
2. Bern, H. A. & Hagadorn, I. R. 1965. In: Structure and Function in the Nervous System of Invertebrate (T. H. Bullock and G. A. Horridge, eds.), Vol. 1: 353–429. W. H. Freeman, San Francisco, California.
3. Clark, R. B. 1956. The neurosecretory system of the polychaete Nephtys and its role in reproduction. XXth Internat. Physiol. Congr. Abstracts of Communications: 178.
4. Czechowicz, K. 1963. Neurosection in leeches and the annual cycle of its changes. Zool. Pol., 13 (3/4): 164–184.
5. Dogra, G. 1968. Studies ‘in situ’ on the neurosecretory system of the earthworm, Pheretima posthuma. J. Zool. Lond., 156: 10–118.