1. Banks, N. L. 1970: Trace fossils from the late Precambrian and Lower Cambrian of Finnmark, Norway. In Crimes, T. P. & Harper, J. C. [editors], Trace fossils. Geol. J. Spec. Issue 3, 19—34. Liverpool.
2. Barrande, J. 1852: Système Silurien du Centre de la Boheme, lere Partie, Crustacés, Trilobites, 1. 935 pp. Praha, Paris.
3. Bastida, R. & Torti, M. R. 1970: Crustaceos isopodos: Serolidae. Résultats scientifiques des Campagnes de la Calypso, 9, 61-105. Paris.
4. Structure and appendages of Trinucleus;Beecher C. E.;Amer. J. Sci., Ser. 3,1895
5. Bergström, J. 1968a: Some Ordovician and Silurian brachiopod assemblages. Lethaia l, 230—237. Oslo.