New York, 17 July 1968 - Internal museum documents Jean Volkmer's letter to Bates Lowry, dated 17 July 1968
Chicago, 21 February 1955 - Management of reproduction rights Marilyn Vaughan's letter to Pablo Picasso
New York, 17 July 1968 - Internal museum documents Jean Volkmer's letter to Bates Lowry, dated 17 July 1968