Lyndon B. Johnson to Richard P. Feynman, October 22, 1965 (telegram) / Richard P. Feynman to Lyndon B. Johnson, October 27, 1965 / Robert R. Wilson to Richard P. Feynman, October 22, 1965 / Richard P. Feynman to Robert R. Wilson, November 23, 1965 / Hans A. Bethe to Richard P. Feynman, October 21, 1965 / Richard P. Feynman to Hans A. Bethe, November 30, 1965