Parmley, D. & Cicimurri, D.J. & Campbell, B. (2003)
Late Eocene sharks of the Hardie Mine local fauna of Wilkinson County, Georgia. Georgia Journal of Science, 61(3), 153–179

Campbell, B. (1951)
The locomotor behavior of spinal elasmobranchs with an analysis of stinging in Urobatis. Copeia, 1951(4), 277–284
DOI: 10.2307/1438312