New York, 10 July 1939 - Institutional correspondence Blanche Mahler's letter to Grace L. McCann Morley
2 May 1939 - Internal institutional documents A draft text for the invitation to the exhibition Picasso's Guernica at the Valentine Gallery, New York
September, 1981 - Management of reproduction rights Memorandum of understanding between the Museum of Modern Art, New York, and Undersigned