Madrid, 17 December 1936 - Institutional correspondence Antonio Rodríguez Morey's, Manuel Azaña's and Jesús Hernández Tomás's letter to Pablo Picasso
Madrid, 26 September 1936 - Internal institutional documents Certificate of appointment for Pablo Picasso as director of the Museo Nacional del Prado
ca. 1952–1957 - Internal museum documents Publicity report for the exhibition Studies for Guernica by the Museum of Cranbrook, New Jersey, addressed to the Travelling Exhibitions Department at the Museum of Modern Art, New York
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