Madrid, 24 September 1936 - Institutional correspondence Letter from Josep Renau to Pablo Picasso, 24 September 1936
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
Paris, 2 November 1979 - Personal correspondence A copy of a letter Claude Picasso wrote to William Rubin, director of Painting and Sculpture at MoMA
Paris, 1 March 1975 - Personal correspondence Claude Picasso's letter to William S. Lieberman, dated 1 March 1975