article: Triceratops
links: Ceratopsia Terrestrial locomotion Nature (journal) Cretaceous Montana Agathaumas Tyrannosaurus Torosaurus Brigham Young University Edward Drinker Cope Late Cretaceous Othniel Charles Marsh Leptoceratops Cretaceous–Paleogene extinction event Arecaceae North America Upper Cretaceous Barnum Brown Greek language Charles R. Knight Stegosaurus Hell Creek Formation Robert Bakker Ceratopsidae