Bletchley Park : Britain's best kept secret.
Brown, Iain Gordon,former owner.
Bletchley Park Trust,publisher.
Title from cover.
Printed label on inside front cover: Ex libris, Iain Gordon Brown, F.S.A.
Great Britain. Government Code and Cypher School.
Great Britain. Government Code and Cypher School.
World War (1939-1945)
Enigma cipher system.
World War, 1939-1945
World War, 1939-1945
World War, 1939-1945
Cryptography.
Electronic intelligence.
Enigma cipher system.
Secret service.