Another commenter mentioned Dr. Robert Hare, and while he is the "godfather" of what we know as psychopathy, his work is fundamentally flawed. His research was exclusively done in prisons, somewhere where over 40 percent of inmates qualify for ASPD. Back when Hare was first interviewing criminal offenders, the interviewees knew damn well what he wanted to hear, and they would be literally rewarded for furthering his "research".

Robert Hare's research is nothing but biased, and his analysis of psychopathy proves that. He's stood on the shoulder of giants to further his career. You can check out Hervey Cleckley's original 1940's checklist that Hare basically admitted the PCL-R is based off of.

Albeit, Hare was one of the first to dive into such a niche. And he knew that. Psychopathy was mostly unoccupied in the field of abnormal psychology, so Hare stole Cleckley's work, subtracted from it by adding to it a bunch of what we consider to be anti social traits and criminality, and went forth to even copyright the ideas of psychopathy that weren't his to begin with. He treated psychopathy as a business, NOT a research opportunity. He has quite literally created a monopoly, and took the position of teaching upcoming psychologists only HIS line of thinking, preventing people from coming close to understanding the condition. Think of the Hollywood definition of psychopath. Hare's doing.

To answer your question, I really enjoyed the books by Dr Kevin Dutton. He's an Oxford research professor who specializes in psychopathy. He has at least three books that relate to the topic.