San Francisco, 12 May 1939 - Institutional correspondence Grace L. McCann Morley's telegram to Sidney Janis
San Francisco, 1 August 1939 - Institutional correspondence Grace L. McCann Morley's letter to Blanche Mahler
New York, 21 August 1939 - Institutional correspondence Evelyn Ahrend's letter to Grace L. McCann Morley, dated 21 August 1939
New York, 9 September 1939 - Institutional correspondence John Sherman's letter to Marcelene Peterson
San Francisco, 12 September 1939 - Institutional correspondence Grace L. McCann Morley's letter to Evelyn Ahrend
Ellen C. Oppler (ed.), <em>Picasso’s Guernica</em>, New York and London: W. W. Norton & Company, 1988, 236–238 - Essay “How Effective Is Social Protest Art? (Vietnam)”
Siracusa, New York, 15 July 1979 - Institutional correspondence Ellen Oppler's letter to Luisa Kreisberg