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, 17 November 1959 - Institutional correspondence A letter from the Groupe d'étudiants d'espagnol to Pablo Picasso
New York, 24 March 1980 - Institutional correspondence A letter from Richard Oldenburg and William Rubin to Javier Tusell