Lull, R.S., 1918, Fossil footprints from the Grand Canyon of the Colorado: American Journal of Science, 4th ser., v. 45, no. 269, p. 337-346. Authors Lull, R.S. Publication Date 1918 Citation American Journal of Science, 4th ser., v. 45, no. 269, p. 337-346. State AZ Province CP County CN Keywords Trace Fossil Vertebrate Paleontology More Keywords Trace Fossil, Vertebrate, Paleontology, AzGeoBib RefNum 6245