Jim Futrell, historian for the National Amusement Park Historical Association (NAPHA), has studied the amusement park industry for over 30 years. Futrell has conducted extensive research and written five books and numerous articles on the subject, including Images of America: Waldameer Park. Dave Hahner is a historian for American Coaster Enthusiasts (ACE). An avid amusement park and roller coaster enthusiast, Hahner has written Images of America: Kennywood, featuring his hometown park in Pittsburgh.