Wall, W.P. & Galton, P.M. (1979). "Notes on pachycephalosaurid dinosaurs (Reptilia: Ornithischia) from North America, with comments on their status as ornithopods". Canadian Journal of Earth Sciences. 16:1176-1186
Maryanska, T., Chapman, R.E., and Weishampel, D.B. (2004). "Pachycephalosauria". In D. B. Weishampel, P. Dodson & H. Osmólska (eds.), The Dinosauria (second edition). University of California Press, Berkeley 464-477