License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Marco Dente. Apollo tending the flocks of Admetus, Apollo seated holding a lyre and flanked by a cow and a dog, a serpent winding around a dead tree at right, ca. 1515–27. The Metropolitan Museum of Art.