New York, 9 September 1981 - Institutional correspondence An internal letter from Richard E. Oldenburg to staff at the Museum of Modern Art, New York
New York, 24 March 1980 - Institutional correspondence A letter from Richard Oldenburg and William Rubin to Javier Tusell
<em>The New York Times</em>, New York, June 13, 1971, 1 - Article “Vietnam Archive: Pentagon Study Traces 3 Decades of Growing U.S. Involvement”