In the 1980s Pether created marvelous cover paintings for a variety of romance novels - regrettably, some of them left untitled in his inventory after his death.  This one is clearly meant for a "wraparound" format paperback - possibly for Sphere, Little Brown, HarperCollins or Fontana (just some of the publishers he was working for during that decade) but who knows?  If you recognize the book, and can source it. . . power to you!  Finely rendered with Pether's eye for details, in great condition, painted in gouache and acrylic on illustration board, image 15.5" x 21.5" and comes with a label attesting to authenticity, signed by Pether's widow, on the back.