HEIDELBERG.- German researcher Veit Probst from Heidelberg University claims he has found proof of the identity of Mona Lisa. Veit Probst stated he found a book that belonged to a friend of da Vinci, Agostino Vespucci. There is a note on the margin of one of the pages that confirms that Lisa del Giocondo, the third wife of a Florentine businessman Francesco del Giocondo, is Mona Lisa. The note is dated October 1503. She has always been considered the most likely subject of the work, but there had never been a definitive confirmation. Probst plans to publish an essay soon. He claims he has independent verification that the Vespucci note is genuine.