Beyond Top Secret Ultra
By: Ewen Montagu. --
Publisher: Coward, McCann & Geoghegan
Published: 1978
Place of publication: New York
Number of pages: 192
Subjects: World War, 1939-1945 -- Cryptography.; World War, 1939-1945 -- Secret service -- Great Britain.
Notes: First published in 1977 under title: Beyond Top Secret U. *** Includes index.

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