16 September 1960 - Internal museum documents A letter from Betsy Jones to Alfred H. Barr Jr., dated 16 September 1960
Madrid, 3 September - Institutional correspondence Carlos Robles Piquer's letter to Javier Tusell, dated 3 September
Madrid, 10 June 1981 - Internal institutional documents A letter from Carlos Robles Piquer to Javier Tusell
Madrid, 19 June 1981 - Institutional correspondence A letter from Carlos Robles Piquer to Javier Tusell, dated 19 June 1981
New York, 6 August 1973 - Institutional correspondence A letter from Betsy Jones to Daniel-Henry Kahnweiler
New York, 18 September 1964 - Institutional correspondence A letter from Betsy Jones to Alfred H. Barr Jr., dated 18 September 1964