A spokesperson for publisher HarperCollins has confirmed to Us Weekly that The Billy Bob Tapes: A Cave Full of Ghosts will feature a small passage written by Jolie.
HarperCollins has touted that the autobiography will include "colorful tales of his modest (to say the least) Southern upbringing, his bizarre phobias (komodo dragons?), his life, his loves (including his heartbreakingly brief marriage to fellow Oscar winner Angelina Jolie), and, of course, his movie career".
Jolie and Thornton were married for three years, after meeting on the set of the movie Pushing Tin.
The couple adopted son Maddox a mere three months before they announced their separation in 2002.
Jolie - who is now in a committed relationship with Brad Pitt - has largely refrained from discussing her marriage to Thornton in public, but the actor said in December 2010 that he is "proud" of his ex-wife.
The Billy Bob Tapes: A Cave Full of Ghosts, co-written by Kinky Friedman, is released in the US on May 15.
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