^ abcdR. Lund and E. Grogan. 2004. Five new euchondrocephalan Chondrichthyes from the Bear Gulch Limestone (Serpukhovian, Namurian E2b) of Montana, USA. Recent Advances in the Origin and Early Radiation of Vertebrates 505–531
^Grogan, E. D., & Lund, R. (2008). A basal elasmobranch, Thrinacoselache gracia n. gen and sp.,(Thrinacodontidae, new family) from the Bear Gulch Limestone, Serpukhovian of Montana, USA. Journal of Vertebrate Paleontology, 28(4), 970–988.
^John-Paul M. Hodnett, David K. Elliott; Carboniferous chondrichthyan assemblages from the Surprise Canyon and Watahomigi formations (latest Mississippian–Early Pennsylvanian) of the western Grand Canyon, Northern Arizona. Journal of Paleontology ; 92 (S77): 1–33. doi:10.1017/jpa.2018.72