Overview
"Floradora", also called Keyword, was a doubly enciphered diplomatic code used by the Germans during the Second World War. The Allies used tabulating equipment, created by IBM, to break the code over period of more than a year in 1941 and 1942.
References
Budiansky, Stephen. Battle of wits: the complete story of codebreaking in World War II, p. 55. Simon and Schuster, 2000
Cryptography
Communications in Germany
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