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 the Smithsonian Archives of American Art as being "among the key documentary images of American modern art". In 1966 the Tate Gallery hosted a large exhibit of his work. Other major institutions, including the Philadelphia Art Museum and the Metropolitan Museum of Art, followed with large showings of Duchamp's work. He was invited to lecture on art and to participate in formal discussions, as well as sitting for interviews with major publications. As the last surviving member of the Duchamp family of artists, in 1967 Duchamp helped to organize an exhibition in Rouen, France, called "Les Duchamp: Jacques Villon, Raymond