Stockholm, 7 June 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 7 June 1956
Stockholm, 11 September 1956 - Institutional correspondence Bo Wennberg's letter to the Stedelijk Museum
Stockholm, 23 October 1956 - Institutional correspondence A letter from Bo Wennberg and K. G. Hulten to Pablo Picasso
Stockholm, 6 May 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 6 May 1956
Stockholm, 20 September 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 20 September 1956
Amsterdam, 24 September 1956 - Institutional correspondence Willem Sandberg's letter to Bo Wennberg, dated 24 September 1956
Stockholm, 1 October 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 1 October 1956
Stockholm, 10 October 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 10 October 1956
Stockholm, 1 October 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 1 October 1956 (copy)
Stockholm, 7 December 1956 - Institutional correspondence Bo Wennberg's letter to Willem Sandberg, dated 7 December 1956
Paris, 12 May 1981 - Institutional correspondence Rafael Fernández Quintanilla's letter to Carlos Robles Piquer
Paris, ca. 1981 - Institutional correspondence A communiqué from Rafael Fernández Quintanilla on the viewpoint of Pablo Picasso's heirs
New York, 20 March 1980 - Internal institutional documents An agreement to deliver Guernica to the Spanish government
Buenos Aires, 28 November 1979 - Institutional correspondence Rafael Fernández Quintanilla's letter to José Joaquín Puig de la Bellacasa
Buenos Aires, 17 September 1979 - Institutional correspondence Rafael Fernández Quintanilla's letter to Javier Tusell, dated 17 September 1979
Paris, 22 November 1980 - Personal correspondence Rafael Fernández Quintanilla’s secret dispatch to Javier Tusell, director-general of Fine Arts