Mougins, 14 November 1970 - Institutional correspondence Pablo Picasso's letter to the New York's Museum of Modern Art
Cambridge, Massachusetts, 20 November 1939 - Personal correspondence Josep Lluís Sert's letter to Pablo Picasso, dated 20 November 1939
Paris, 3 October 1948 - Institutional correspondence Pablo Picasso's letter to Alfred H. Barr Jr., dated 3 October 1948
Paris, 26 November 1948 - Institutional correspondence A letter from Pablo Picasso to Alfred H. Barr Jr., dated 26 November 1948
New York, 1939 - Exhibition catalogue Catalogue of the exhibition organised by the American Artists' Congress at the Valentine Gallery, for the benefit of Spanish refugees. Signed by Juan Negrín and Julio Álvarez del Vayo