"Pretty Boy Floyd", by Larry McMurty (of "Lonesome Dove" fame) and Diana Ossana.
The true facts of any famous person will always be disputed and the life and times of Charley "Pretty Boy" Floyd has many that can not to proven and this novel is written with the known facts, innuendos, and a certain amount of artistic license.
One fact is certain, times were hard in depression era Oklahoma. The novel conjours up the "Joad" family in "Grapes of Wrath". Charley helps enough poor people with food and tore up land mortgages at banks that his was often refereed as the "Robin Hood Bandit".
Pretty Boy Floyd had a wife and a son, a steady girl friend, plus an older woman (lover and mentor in his criminal live), and George Birdwell (his partner in crime).
Charley and George robbed so many banks in Oklahoma that the bank insurance rated doubled in a year.
This a not a book for the prudish but I found it a very intriguing read. After reading the book, I checked out some of the other facts and legends of Floyd online as I knew very little about him before I read the book.