20 February 1980 - Institutional correspondence A letter from Ricardo de la Cierva Hoces to Adolfo Suárez
Madrid, 28 June 1980 - Institutional correspondence Ricardo de la Cierva Hoces' letter to Javier Tusell
New York, 24 September 1957 - Institutional correspondence Virginia Pearson's letter to Alfred H. Barr Jr.
New York, 5 November 1957 - Institutional correspondence Virginia Pearson's letter to Katharine Kuh, dated 5 November 1957
New York, 20 September 1957 - Institutional correspondence Virginia Pearson's letter to Katharine Kuh, dated 20 September 1957