Amsterdam, 25 January 1956 - Transport documents M. Winter's letter to Robert Giron, dated 25 January 1956
Amsterdam, 25 January 1956 - Institutional correspondence M. Winter's letter to Robert Giron, dated 25 January 1956
New York, 3 September 1981 - Internal institutional documents Inventory and conservation report on the works collected by New York's Museum of Modern Art to be sent to Spain
New York, 8 September 1981 - Internal institutional documents A confidential and private document signed by Álvaro Martínez-Novillo and José María Cabrera in New York