A 'Mona Lisa' mystery

A Swiss foundation on Thursday unveiled what it said was an earlier version of the "Mona Lisa" painted by Leonardo da Vinci, although some experts said the claim was unlikely. Before carefully pulling back long velvet white drapes to reveal a radiant painting of what looks like a younger version of the Mona Lisa displayed in the Louvre, the Zurich-based Mona Lisa Foundation said it had evidence the work had indeed been executed by the Italian master