This primary source comes from the Collection DDE-WHOSS: White House Office, Office of the Staff Secretary: Records of Paul T. Carroll, Andrew J. Goodpaster, L. Arthur Minnich, and Christopher H. Russell.
Full Citation: Memorandum for General Persons; 7/5/1960; Intelligence Matters (15); Alphabetical Subject Files, 1953 - 1961; Collection DDE-WHOSS: White House Office, Office of the Staff Secretary: Records of Paul T. Carroll, Andrew J. Goodpaster, L. Arthur Minnich, and Christopher H. Russell; Dwight D. Eisenhower Library, Abilene, KS. [Online Version, https://www.docsteach.org/documents/document/state-u2-opposition, May 15, 2024]