Descriptions of New Crinoidea and Echinoidea, from the Carboniferous Rocks of the Western States, with a Note on the Genns Onychasterv. 21Academy of Natural Sciences67-83
Meek, F. B. and Worthen, A. H. 1869. "Descriptions of New Crinoidea and Echinoidea, from the Carboniferous Rocks of the Western States, with a Note on the Genns Onychaster." Proceedings of the Academy of Natural Sciences of Philadelphia, 21 67–83.