1. Aldrich, J. C., W. Crowe, M. Fitzgerald, M. Murphy, C. McManus, B. Magennis and D. Murphy, 1980. Analysis of environmental gradients and patchiness in the distribution of the epiphytic marine hydroid Clava squamata. Mar. Ecol. Prog. Ser. 2: 293–301.
2. Begon, M., J. L. Harper and C. R. Townsend, 1986. Ecology: individuals, population and communities. Blackwell Sci. Publ., Boston, 851 pp.
3. Beklemishev, W. N., 1969. Principles of Comparative Anatomy of Invertebrates, 1: Promorphology. Oliver and Boyd, Edinburgh, 490 pp.
4. Boero, F., 1984. The ecology of marine hydroids and effects of environmental factors: a review. P.S.Z.N. I, Mar. Ecol. 5: 93–118.
5. Brock, M. A., 1970. Ultrastructural studies on the life cycle of a short-lived metazoan, Campanularia flexuosa. II. Structure of the old adult. J. ultrastruct. Res. 32: 118–141.