License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Adriaen Collaert. Plate 1: equestrian statue of Julius Caesar, seen from the front, with a scene of a naval battle on pedestal below, from 'Roman Emperors on Horseback', ca. 1587–89. The Metropolitan Museum of Art.