Madrid, 17 February 1986 - Institutional correspondence Letter from Justino Azcárate to Carmen Crespo
Paris, 5 January 1953 - Institutional correspondence Letter from the Assemblé National of France to Pablo Picasso
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