Milan, 4 August 1953 - Institutional correspondence A letter from Fernanda Wittgens to Willem Sandberg, dated 4 August 1953
Milan, 12 August 1953 - Institutional correspondence Fernanda Wittgens' letter to Willem Sandberg, dated 12 August 1953
Milan, 7 October 1953 - Institutional correspondence A letter from Fernanda Wittgens to Willem Sandberg, dated 7 October 1953
New York, 8 April 1981 - Press release and communication A press release from New York's Museum of Modern Art concerning a Spanish delegation's request to send Guernica to Spain
6 September 1992 - Newspapers The Reina Sofía presents its Collection and becomes the century's museum of Spanish art