License, verbatimCC0
The Metropolitan Museum of Art: Open Access, Creative Commons Zero (CC0). Flagged isPublicDomain=true in the museum's own record.
Four Icons from a Pair of Doors (Panels), possibly part of a Polyptych: John the Theologian and Prochoros, the Baptism (Epiphany), Harrowing of Hell (Anastasis), and Saint Nicholas. early 15th century. The Metropolitan Museum of Art.