Pradel, A. & Tafforeau, P. & Maisey, J.G. & Janvier, P. (2011)
A New Paleozoic Symmoriiformes (Chondrichthyes) from the Late Carboniferous of Kansas (USA) and Cladistic Analysis of Early Chondrichthyans.
PLoS ONE, 6(9), Article e24938 DOI: 10.1371/journal.pone.0024938