Charles Bremner | The Times | 29th September 2017
Materials technology is upending many agreed art attributions. It turns out that a known, but obscure, Renaissance sketch may have been by none other than – gasp – Leonardo. Experts are almost certain that he painted a (lost) nude version of the Mona Lisa. Some evidence suggests that the sketch in question was part of his preparation for that work. All will be revealed in an exhibition planned for 2019.