 A version of "Mona Lisa" known as ("Woman by Leonardo da Vinci's hand") held in Madrid's Museo del Prado was for centuries considered to be a work by Leonardo.However, since its restoration in 2012, it is considered to have been executed by one of Leonardo's pupils in his studio at the same time as "Mona Lisa" was being painted.The Prado's conclusion that the painting is probably by Salaì (1480–1524) or by Melzi (1493–1572) has been called into question by others.