David Hawcock was the paper engineer for Universe's "New York Pop-Up Book" and "The California Pop-Up Book," Peter Riley has written nearly 200 books for textbook publication on such diverse subjects as astronomy, zoology, history, and religion. Current titles Dinosaurs, Pirates, and Castles are a part of Riley's Hot Topics series for Scholastic. Dr. Thorston Opper is a curator of Greek and Roman Antiquities for The British Museum.