REFERENCES
- Richard J. Aldrich, GCHQ: The Uncensored Story of Britain’s Most Secret Intelligence Agency (London: HarperCollins, 2010)
- Professor John Ferris is to publish an official history for the centenary in 2019.
- Peter Wright, with Paul Greengrass, Spycatcher: The Candid Autobiography of a Senior Intelligence Officer (New York: Viking, 1987).