Peter Larson is founder and president of the Black Hills Institute of Geological Research in Hill City, South Dakota, whose staff was responsible for excavating the T. rex known as "Stan." He lives in Hill City, South Dakota.
Kenneth Carpenter is the dinosaur paleontologist for the Denver Museum of Nature and Science. He is author of Eggs, Nests, and Baby Dinosaurs (IUP, 2000) and editor of The Carnivorous Dinosaurs (IUP, 2005) and The Armored Dinosaurs (IUP, 2001). He lives in Aurora, Colorado.