Brussels, 10 November 1955 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 10 November 1955
Brussels, 17 February 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 17 February 1956
Brussels, 25 February 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 25 February 1956
Brussels, 28 March 1956 - Insurance documents Robert Giron's letter to Willem Sandberg, dated 28 March 1956
Brussels, 10 April 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 10 April 1956
Brussels, 4 April 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 4 April 1956
Brussels, 7 May 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 7 May 1956
Brussels, 6 December 1956 - Institutional correspondence Robert Giron's letter to Willem Sandberg, dated 6 December 1956
Madrid, 22 April 1976 - Internal institutional documents A report by Joaquín de la Puente on the ownership of Guernica and the negotiation possibilities with the Museum of Modern Art, New York
Madrid, 10 September 1981 - Internal museum documents Certificate for the reception of Guernica, and its stretcher and related works
Brussels, 22 December 1955 - Institutional correspondence Robert Giron's letter to Alfred H. Barr Jr.