São Paulo, 28 December 1953 - Institutional correspondence Francisco Matarazzo Sobrinho's letter to Daniel-Henry Kahnweiler
São Paulo, 14 February 1954 - Institutional correspondence Francisco Matarazzo Sobrinho's letter to Pablo Picasso, dated 14 February 1954
São Paulo, 4 February 1954 - Institutional correspondence Francisco Matarazzo Sobrinho's letter to Pablo Picasso, dated 4 February 1954
Madrid, 31 July, and Cambridge, Massachusetts, 31 August 1981 - Institutional correspondence Álvaro Martínez Novillo's letter to Josep Lluís Sert, with reply
Madrid, 29 May and 10 June 1981 - Institutional correspondence A letter from Felipe Cons Gorostola to Álvaro Martínez Novillo, and reply
New York, 3 September 1981 - Internal institutional documents Inventory and conservation report on the works collected by New York's Museum of Modern Art to be sent to Spain
Madrid, 8 February 1982 - Institutional correspondence A letter from Álvaro Martínez Novillo to Pedro J. Ramírez
São Paulo, 26 December 1952 - Institutional correspondence Francisco Matarazzo Sobrinho's letter to Pablo Picasso, dated 26 December 1952
New York, 8 September 1981 - Internal institutional documents A confidential and private document signed by Álvaro Martínez-Novillo and José María Cabrera in New York