Paris, OCT 22 (AP/UNB) — Much about Leonardo Da Vinci remains an enigma: the smile of the "Mona Lisa"; why the world's most famous painter left so many works unfinished; and more recently, who bought the contentious "Salvator Mundi."

Paris, Oct 22 (AP/UNB) — Much about Leonardo Da Vinci remains an enigma: the smile of the "Mona Lisa"; why the world's most famous painter left so many works unfinished; and more recently, who bought the contentious "Salvator Mundi."