The Paleogeographic and Stratigraphic Distribution of Ceratopsids (Ornithischia) in the Upper Judith River Group of Western Canada Brinkman, Donald B. ; Ryan, Michael J. ; Eberth, David A. Abstract Publication: Palaios Pub Date: April 1998 DOI: 10.2307/3515487 Bibcode: 1998Palai..13..160B