In October 2013, Jean-Pierre Isbouts published his book "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 of the same name 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, modifying his technique or the second. 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. In support of his assertion of authorship, Isbouts noted the similarities of the Raphael drawing and the work done by Asmus, as well as confirmation by other examiners that the canvas and paints were the appropriate age, and that the painting exhibited "downward-extending brush strokes from left to right... consistent with the work of a left-handed artist", as Leonardo was.