UBAGHS, Georges; CASTER, K. E. Part S, Echinodermata 1, vol. 1 & 2 , Ch. 4, p. 455 - 565. Treatise on Invertebrate Paleontology, [S. l.], 1968. DOI: 10.17161/dt.v0i0.5637. Disponível em: https://journals.ku.edu/InvertebratePaleo/article/view/5637. Acesso em: 9 apr. 2025.