St.John, O.H. & Worthen, A.H. (1875)
Palaeontolgoy of Illinois. Descriptions of fossil fishes. Geological Survey of Illinois, 6, 245–488

Maisey, J.G. (1983)
Some Pennsylvanian chondrichthyian spines from Nebraska. Transactions of the Nebraska Academy of Sciences, 11, 81–84

Schnetz, L. & Dunne, E.M. & Feichtinger, I. & Butler, R.J. & Coates, M.I. & Sansom, I.J. (2024)
Rise and diversification of chondrichthyans in the Paleozoic. Paleobiology, 50(2), 271–284
DOI: 10.1017/pab.2024.1

Schnetz, L. & Dunne, E.M. & Feichtinger, I. & Butler, R.J. & Coates, M.I. & Sansom, I.J. (2024)
Rise and diversification of chondrichthyans in the Paleozoic. Paleobiology, 50(2), 271–284
DOI: 10.1017/pab.2024.1