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* Good, I.J., and Cipher A. Deavours, afterword to Marian Rejewski, "How Polish Mathematicians Deciphered the Enigma", Annals of the History of Computing, July 1981.

A revised and augmented translation of W kręgu enigmy, Warsaw, Książka i Wiedza, 1979, supplemented with appendices by Marian Rejewski

Largely an abridgment of , minus Rejewski's appendices, which have been replaced with appendices of varying quality by other authors