By John K. Gurwell. That quote on the top of the back cover is from Wayne Henley, who killed Dean Corll in self-defense, an act which led to the literal unearthing of dozens of Corll's victims.
This vintage paperback is nearly a half-century old, and looks it -- edgewear, spine cracks, stickers, a previous owner's name on the inside cover -- but it's also rather rare, so if you're a Corll case completist, grab this one.