This was an early test print of the mass-produced lithographs that would later be sent out by the studio in response to Snow White fan mail. This test print (done on drawing paper, complete with ink drops, rather than the later card stock, and minus the production stamp) was personally gifted to Disney cousin Rilla Hussey of Ellis, Kansas, by Walt himself.
Snow White and the Seven Dwarfs Lithograph Test Print (1937)
