1. Adiyodi, K. G., 1988. Annelida. In K. G. Adiyodi, R. G. Adiyodi (eds), Reproductive Biology of Invertebrates, vol III, Accessory Sex Glands. J. Wiley, Sons, New York: 189–250.
2. Allen, E. J., 1905. The anatomy of Poecilochaetus, Claparède. Q. J micr. Sci. 48: 79–151.
3. Ax, R, 1989. Homologie in der Biologie - ein Relationsbegriff im Vergleich von Arten. Zool. Beitr. N.F. 32: 487–496
4. Bartolomaeus, T., 1989a. Ultrastructure and development of the nephridia in Anaitides mucosa ( Annelida, Polychaeta). Zoomorphology 109: 15–32.
5. Bartolomaeus, T., 1989b. Ultrastructure and relationship between protonephridia and metanephridia in Phoronis mülleri ( Phoronida ). Zoomorphology 109: 113–122.