A Gigantic Shark from the Lower Cretaceous Duck Creek Formation of Texas Frederickson, Joseph A. ; Schaefer, Scott N. ; Doucette-Frederickson, Janessa A. Abstract Publication: PLoS ONE Pub Date: June 2015 DOI: 10.1371/journal.pone.0127162 Bibcode: 2015PLoSO..1027162F