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.