1. Alvarino, A. (1965): Chaetognaths. — Oceanogr. mar. Biol. Ann. Rev.,3: 115–194; London.
2. Bayer, F. M. &Owre, H. B. (1968): The free-living lower invertebrates. — 229 pp.; New York.
3. Beauchamp, P. de (1960): Classe des chétognathes. — In: Grasse, P.-P. [Ed.]: Traité de Zoologie,5 (2); 1500-1520; Paris.
4. Beklemischev, W. N. (1963): On the relationship of the Turbellaria to other groups of the animal kingdom. — In: Dougherty, E. C. [Ed. J: The lower Metazoa. Comparative biology and phylogeny, 234–244; Berkeley and Los Angeles.
5. - (1969): Principles of comparative anatomy of invertebrates. — 490 pp. (1), 529 pp. (2); Edinburgh. [Engl, transl. of 3rd (1964) Russ. ed.]