A series of paperbacks, published in the 1940's and 1950's with a map of the scene of the crime on the back cover.
If you are interested in seeing a very extensive collection of Dell Map Back covers, take a look at this site.
Ruth Belew - An artist for Dell who did the maps. Other artists did the covers.
Collecting Dell mapbacks - an article by Rich Rennicks in the New Antiquarian blog, July 9, 2020.
Putting Dell on the Map - a history of Dell paperbacks by William H. Lyles. Published in 1983 by Greenwood Press. This information is from GoodReads.
Who is Philip Ketchum? The very first paperback issued in what would become the Dell Map Back series was titled The Body in the Library. It had no map on the back, and it was written by Philip Ketchum. Who? It seems that Philip Ketchum was a writer of Western novels, and that this is his only mystery novel. The only information that I found about him is at Goodreads.
This site is maintained by Linda Bertland, retired school librarian,
Philadelphia, PA. Please address any comments, additions, or corrections to info@sldirectory.com