Michael J. Ryan, David C. Evans, Kieran M. Shepherd: A New Ceratopsid from the Foremost Formation (Middle Campanian) of Alberta. In: Canadian Journal of Earth Sciences, Bd. 49, Nr. 11, 2012, ISSN0008-4077, S. 1251–1262, doi:10.1139/e2012-056.
google.at
books.google.at
A. T. McDonald & J. R. Horner: New Material of "Styracosaurus" ovatus of the Two Medicine Formation of Montana. In: M. J. Ryan, B. J. Chinnery-Allgeier & D. A. Eberth: New Perspectives on Horned Dinosaurs: The Royal Tyrrell Museum Ceratopsian Symposium, S. 156–168, Indiana University Press, 2010. ISBN 978-0-253-35358-0(Leseprobe)
Michael J. Ryan, David C. Evans, Kieran M. Shepherd: A New Ceratopsid from the Foremost Formation (Middle Campanian) of Alberta. In: Canadian Journal of Earth Sciences, Bd. 49, Nr. 11, 2012, ISSN0008-4077, S. 1251–1262, doi:10.1139/e2012-056.