License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Stefano della Bella. A hunting trophy, two wild boar heads above, two deer heads below, from "Ornaments or Grotesques" (Ornamenti o Grottesche), ca. 1650–56. The Metropolitan Museum of Art.