Mona Lisa
The painting is thought to be a portrait of Lisa Gherardini, the wife of Francesco del Giocondo, and is in oil on a white Lombardy poplar panel. It had been believed to have been painted between 1503 and 1506; however, Leonardo may have continued working on it as late as 1517. Recent academic work suggests that it would not have been started before 1513. It was acquired by King Francis I of France and is now the property of the French Republic, on permanent display at the Louvre Museum in Paris since 1797.
Isleworth Mona Lisa
In October 2013 Jean Pierre Isbouts published a book titled "The Mona Lisa Myth" examining the history and events behind the Louvre and Isleworth paintings and confirmed the latter's attribution to Leonardo. A companion film was released in March 2014. In April 2014, Albert Sauteur examined the perspective used to execute the "Isleworth Mona Lisa" and the "Mona Lisa" in the Louvre, and concluded that Leonardo painted both works. In July 2014 "The Mona Lisa Mystery" premiered on the PBS television station's series "Secrets of the Dead". This documentary investigated, at length, the authenticity of the Isleworth painting.