books.google.com - Always study with the most up-to-date prep! Look for Police Exams Prep 2018-2019, ISBN 9781506229690, on sale April 3, 2018....https://books.google.com/books/about/John_Douglas_s_Guide_to_the_Police_Offic.html?id=l2EVcAAACAAJ&utm_source=gb-gplus-shareJohn Douglas's Guide to the Police Officer Exams
John Douglas, a highly regarded figure in the field of law enforcement, founded and ran the FBI’s Investigative Support Unit for 15 years before serving an additional ten years as an FBI field agent and recruiter. He is the author of several books about famous FBI cases and was the inspiration for the character of Jack Crawford in Silence of the Lambs and Red Dragon. Douglas lives in New York City.