Brussels, 28 March 1956 - Insurance documents Robert Giron's letter to Willem Sandberg, dated 28 March 1956
Amsterdam, 1956 - Internal museum documents A checklist for the Guernica studies, insurance costs and notes.
Amsterdam, 1956 - Internal museum documents A packing list of studies for Guernica with titles and measurements
New York, 6 July 1939 - Institutional correspondence Alfred H. Barr Jr.'s letter to Pablo Picasso, dated 6 July 1939
New York, 10 July 1939 - Institutional correspondence Evelyn Ahrend's letter to Marcelene Peterson, dated 10 July 1939