New York, 9 September 1981 - Institutional correspondence An internal letter from Richard E. Oldenburg to staff at the Museum of Modern Art, New York
Paris, 9 June 1953 - Institutional correspondence Maurice Jardot's letter to Francisco Matarazzo Sobrinho
New York, 24 March 1980 - Institutional correspondence A letter from Richard Oldenburg and William Rubin to Javier Tusell
23 February 1954 - Institutional correspondence Maurice Jardot's letter to Pablo Picasso, dated 23 February 1954
20 September 1954 - Institutional correspondence Maurice Jardot's letter to Jaime Sabartés, dated 20 September 1953