Zurich, 12 December 1955 - Institutional correspondence A letter from Klaus Herdeg to Willem Sandberg
Madrid, 11 September 1980 - Institutional correspondence Javier Tusell's letter to José Pedro Pérez-Llorca
Madrid, 23 and 25 September 1980 - Institutional correspondence Alejandro de Muns' letter to Javier Tusell, with reply
Madrid, 11 December 1980 - Internal institutional documents Javier Tusell's report on negotiations for the transfer of Guernica
Madrid, 1 June 1981 - Internal institutional documents An internal letter from Javier Tusell to Íñigo Cavero
ca. 1981 - Internal institutional documents A report by Javier Tusell, director-general of Fine Arts on his trip to France and his visit to Pablo Picasso's heirs
Madrid, 25 February and Mexico City, 16 April 1981 - Institutional correspondence Javier Tusell's letter to Wenceslao Roces, and the reply
Madrid, 7 and 19 January 1981 - Institutional correspondence A letter from Enrique Calduch 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
New York, 20 March 1980 - Internal institutional documents An agreement to deliver Guernica to the Spanish government
Madrid, 19 October 1979 - Institutional correspondence Javier Tusell's letter to Horacio Sáenz Guerrero
Madrid, 10 September 1981 - Internal museum documents Certificate for the reception of Guernica, and its stretcher and related works
20 January 1981 - Personal notes A photocopied note on Guernica, written by the director-general of Fine Arts, Javier Tusell, and dated incorrectly as 20 January 1981 when, according to its content, the date is more likely to be 20 August
