This primary source comes from the General Records of the Department of State.
Full Citation: Letter from John Foster Dulles to Senator Lyndon B. Johnson Regarding the Special Senate Committee on Space and Astronautics; 1959; 14. Scientific Research & Development: 14B Outer Space: Outer Space - General, 1959 - 1959; General Records Relating to Atomic Energy Matters, 1948 - 1962; General Records of the Department of State, Record Group 59; National Archives at College Park, College Park, MD. [Online Version, https://www.docsteach.org/documents/document/dulles-to-johnson-regarding-space, April 26, 2024]