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).
Stephan Fridolin, (author), Michael Wolgemut, and Wilhelm Pleydenwurff. Der Schatzbehalter oder Schrein der waren Reichtümer des Heils und ewige Seligkeit, 1491. National Gallery of Art, Washington.