Colossus: The secrets of Bletchley Park's code-breaking computers

The Secrets of Station X: How the Bletchley Park codebreakers helped win the war

Enigma: The Battle for the Code

The Secret Lives of Codebreakers: The Men and Women Who Cracked the Enigma Code at Bletchley Park

Seizing the Enigma: The Race to Break the German U-Boat Codes, 1933-1945