Notes
- Hinsley , F.H. , Thomas , E.E. , Ranson , C.F.G. and Knight , R.C. 1981 . British Intelligence in the Second World War: Its Influence on Strategy and Operations , Vol. 2 , 28 London : HMSO .
- Erskine , Ralph and Weierud , Frode . 1987 . ‘Naval Enigma: M4 and its Rotors’ . Cryptologia , 11 ( 4 ) Oct. : 235
- Bloch , Gilbert and Erskine , Ralph . 1986 . ‘Enigma: The Dropping of Double Encipherment’ . Cryptologia , 10 ( 3 ) July : 134
- Erskine , Ralph . 1989 . ‘Naval Enigma ‐ A Missing Link’ . Int. Jnl. of Intelligence and Counterintelligence , 3 ( 4 ) : 501
- Kahn , David . 1991 . Seizing the Enigma: The Race to break the U‐boat Codes , 285 Boston : Houghton Mifflin .
- Good , Jack . 1993 . “ ‘Enigma and Fish’ ” . In Codebreakers: The Inside Story of Bletchley Park , Edited by: Stripp , Alan and Hinsley , F.H. 155 Oxford : OUP .
- Hinsley . 1984 . British Intelligence in the Second World War , Vol. 3(1) , 486 London : HMSO .
- Welchman , Gordon . 1982 . The Hut Six Story: Breaking the Enigma Codes , 65 NY/London : McGraw‐Hill/Allen Lane .
- Hinsley . 1988 . British Intelligence in the Second World War , Vol. 3(2) , 953 957 London : HMSO .
- Bloch and Erskine . “ ‘The Dropping of Double Encipherment’ ” . 137 (note 6)
- Hinsley . British Intelligence , 2 667
- Hinsley . British Intelligence , 2 28
- Rejewski , Marian . 1984 . “ ‘How the Polish Mathematicians Broke Enigma’ ” . In Enigma , Edited by: Kozaczuk , Wladyslaw . 246 Frederick, MD/London : U. Publications of America/Arms & Armour Press .
- Rejewski , Marian . “ ‘Summary of Our Methods for Reconstructing Enigma and Reconstructing Daily Keys and of German Efforts to Frustrate Those Methods’ ” . 242 ibid.
- Erskine , Ralph . 1989 . ‘The Soviets and Naval Enigma: Some Comments’ . Intelligence and National Security , 4 ( 3 ) July : 503
- Jukes , Geoffrey . April 1988 . “ ‘More on the Soviets and Ultra’ ” . Vol. 3/2 , April , 375 ibid.
- Hinsley . British Intelligence , 2 611
- Kozaczuk , Wladyslaw . 1989 . Geheim‐Operation Wicher , 339 Koblenz : Bernard & Graefe Verlag .