David D. Gillette, Ph.D., is State Paleontologist for Utah, and Distinguished Lecturer 1994-95 for the American Association of Petroleum Geologists. Dr. Gillette is also Trustee and Principal Investigator of the Southwest Paleontology Foundation in Albuquerque and was formerly the Curator of Paleontology at the New Mexico Museum of Natural History. He is the coeditor of Dinosaur Tracks and Taces  and coauthor of Glyptodonts of North America.
Mark Hallett, is a well-known illustrator of prehistoric animals and their environments. His work has graced the pages of Life, Smithsonian,  and Natural History  and has been featured in internationally televised programs including Smithsonian World, Nova,  and a series on prehistoric life by David Attenborough.