Horner, J.; Goodwin, M.; Sereno, P. (2009). Sereno, Paul. ed. "Extreme cranial ontogeny in the upper cretaceous dinosaur pachycephalosaurus". PLoS ONE 4 (10): e7626.doi:10.1371/journal.pone.0007626
Holtz, Thomas R. Jr. (2012) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,Winter 2011 Appendix. (页面存档备份,存于互联网档案馆)
Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,Winter 2010 Appendix. (页面存档备份,存于互联网档案馆)
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Holtz, Thomas R. Jr. (2012) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,Winter 2011 Appendix. (页面存档备份,存于互联网档案馆)
Holtz, Thomas R. Jr. (2011) Dinosaurs: The Most Complete, Up-to-Date Encyclopedia for Dinosaur Lovers of All Ages,Winter 2010 Appendix. (页面存档备份,存于互联网档案馆)