Readymades of Marcel Duchamp to turn up any identical matches to photographs of the originals. However, there are accounts of Walter Arensberg and Joseph Stella being with Duchamp when he purchased the original "Fountain" at J. L. Mott Iron Works. Such investigations are hampered by the fact that few of the original "readymades" survive, having been lost or destroyed. Those that still exist are predominantly reproductions authorized or designed by Duchamp in the final two decades of his life. Shearer also asserts that the artwork "L.H.O.O.Q." which is recorded to be a poster-copy of the "Mona Lisa" with a moustache drawn on it, is
Marcel Duchamp photoelectric cells underneath the chessboard, triggered sporadically by normal game play. On choosing a career in chess, Duchamp said, "If Bobby Fischer came to me for advice, I certainly would not discourage him—as if anyone could—but I would try to make it positively clear that he will never have any money from chess, live a monk-like existence and know more rejection than any artist ever has, struggling to be known and accepted." Duchamp left a legacy to chess in the form of an enigmatic endgame problem he composed in 1943. The problem was included in the announcement for Julian Levi's