I'm currently reading The Black Dahlia Avenger by Steve Hodel. The author is a retired LAPD detective who believes that his father killed Elizabeth Short in 1947, and likely several other girls during that general time period. He found a picture of Short among his fathers belongings after he passed away and started investigating to find out how they knew each other. There are 2 books related to the Dahlia case, as well as two books called Most Evil, where Mr Hodel goes into how he came to believe his father may have also been the Zodiac Killer. I read two Dahlia and first Zodiac book several years ago for a Criminal Psychology class that I was taking, re-reading the series because the second Zodiac book came out and I want to refresh my memory with the details.