This primary source comes from the Collection DDE-1417: Records of the Office of the Special Assistant for National Security Affairs (Eisenhower Administration).
Full Citation: Letter, J. Edgar Hoover to Dillon Anderson; 11/22/1955; Collection DDE-1417: Records of the Office of the Special Assistant for National Security Affairs (Eisenhower Administration). [Online Version, https://www.docsteach.org/documents/document/2-letter-j-edgar-hoover-to-dillon-anderson, March 29, 2024]