License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
José Guadalupe Posada. Two elegantly dressed skeletons walking, from a broadside entitled, 'El Gran Panteon Amoroso,' published by Antonio Vanegas Arroyo., ca. 1894. The Metropolitan Museum of Art.