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).
Italian 16th Century, after Michelangelo, published by Vincenzo Luchino. Forma Partis Templi Divi Petri [Exterior Section of Saint Peter's Basilica], 1564. National Gallery of Art, Washington.