Articulata. Moore, R.C.; Teichert, C.[Eds]. Treatise on invertebrate paleontology. Part T. Echinodermata 2. Volume 3., University of Kansas & Geological Society of America, Inc., Boulder, Colorado & Lawrence, Kansas, 1978: T813-T1027. Chapter pagination: T813-T927. T833 [Zoological Record Volume 116]