File:Pachycephalosaurus skull.pngDescriptionPachycephalosaurus skull.png English: The holotype adult skull of Pachycephalosaurus "reinheimeri" (DMNS 469). Polski: Czaszka holotypu Pachycephalosaurus
File:Pachycephalosaurus UDL.png4.0 Creative Commons Attribution-Share Alike 4.0 truetrue English Pachycephalosaurus: "Thick-headed lizard" Late Cretaceous, North America author name
File:Pachycephalosaurus ontogeny.pngDescriptionPachycephalosaurus ontogeny.png English: Cranial ontogenetic sequence of Pachycephalosaurus wyomingensis with morphological landmarks highlighted