Barry Cox, Colin Harrison, R.J.G. Savage, and Brian Gardiner. (1999): The Simon & Schuster Encyclopedia of Dinosaurs and Prehistoric Creatures: A Visual Who's Who of Prehistoric Life. Simon & Schuster.
David Norman. (2001): The Big Book Of Dinosaurs. pg. 228, Walcome books.
After the Dinosaurs: The Age of Mammals (Life of the Past) by Donald R. Prothero
The Evolution of Artiodactyls by Donald R. Prothero and Scott E. Foss
Vertebrate Palaeontology by Michael J. Benton and John Sibbick
Evolving Eden: An Illustrated Guide to the Evolution of the African Large Mammal Fauna by Alan Turner and Mauricio Anton
Classification of Mammals by Malcolm C. McKenna and Susan K. Bell \
The Book of Life: An Illustrated History of the Evolution of Life on Earth, Second Edition by Stephen Jay Gould
World Encyclopedia of Dinosaurs & Prehistoric Creatures: The Ultimate Visual Reference To 1000 Dinosaurs And Prehistoric Creatures Of Land, Air And Sea... And Cretaceous Eras (World Encyclopedia) by Dougal Dixon
Eyewitness: Prehistoric Life by William Lindsay
Walker's Mammals of the World (2-Volume Set) (Walker's Mammals of the World) by Ronald M. Nowak
Horns, Tusks, and Flippers: The Evolution of Hoofed Mammals by Donald R. Prothero and Robert M. Schoch