License, verbatimPD
The National Gallery of Art: open access image with no usage restrictions under the NGA's open access policy (openaccess=1 in the Gallery's published_images dataset).
Maurice Denis, Ambroise Vollard (publisher), Auguste Clot (technician). Les crépuscules ont une douceur d'ancienne peinture, 1892/1899. National Gallery of Art, Washington.