16 February 1976 - Institutional correspondence Report for the National Commission of Artistic Heritage
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
22 November 1980 - Institutional correspondence Rafael Fernández Quintanilla's letter to Javier Tusell, dated 22 November 1980
New York, 31 August 1981 - Institutional correspondence John Koegel's letter to Richard E. Oldenburg, dated 31 August 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
New York, 16 October 1981 - Institutional correspondence John Koegel's letter to Javier Tusell, dated 16 October 1981
Madrid, 19 October 1979 - Institutional correspondence Javier Tusell's letter to Horacio Sáenz Guerrero
Buenos Aires, 17 September 1979 - Institutional correspondence Rafael Fernández Quintanilla's letter to Javier Tusell, dated 17 September 1979
Salamanca, 22 July 1981 - Institutional correspondence A letter from Mª Teresa Díez de los Ríos to Javier Tusell
Madrid, 4 February 1981 - Institutional correspondence A letter from Javier Tusell to Íñigo Cavero, dated 4 February 1981
Madrid, 13 November 1980 - Institutional correspondence A letter from Javier Tusell to Íñigo Cavero, dated 13 November 1980
Madrid, 17 September 1980 - Institutional correspondence A letter from José Mario Armero to Íñigo Cavero
New York, 30 August 1979 - Institutional correspondence A letter from Ethen Shein to Richard E. Oldenburg
Madrid, 12 February 1976 - Institutional correspondence A letter from the director-general of Cultural Heritage
Madrid, 16 February 1976 - Institutional correspondence A report from the National Commission of Artistic Heritage on the documents needed to recover Guernica.
Madrid, 25 February and Mexico City, 16 April 1981 - Institutional correspondence Javier Tusell's letter to Wenceslao Roces, and the reply