Wagner C. D., Durham J. W. (1966) Holasteroids, Treatise on Invertebrate Paleontology,Part U Echinodermata 3. The Geological Society of America and The University of Kansas Press 2, U523-U543
Kroh A., Smith A. B. (2010) The phylogeny and classification of post-Palaeozoic echinoids, Journal of Systematic Palaeontology 8 2, 147-212 doi:10.1080/14772011003603556
Benton, M.J. (ed). (1993). The Fossil Record 2. Chapman & Hall, London, 845 pp.