A Probable Tyrannosaurid Track from the Hell Creek Formation (Upper Cretaceous), Montana, United States Manning, P. L. ; Ott, C. ; Falkingham, P. L. Abstract Publication: Palaios Pub Date: October 2008 DOI: 10.2110/palo.2008.p08-030r Bibcode: 2008Palai..23..645M