The Ultra Secret by F.W. Winterbotham

The Ultra Secret by F.W. Winterbotham
US$5.22

Paperback. Condition: Good. 1975. Dell.

Operation Ultra was designed to intercept & decode German signals sent using Enigma, the top-secret German cypher machine. F.W. Winterbotham, was the man responsible for the organization, distribution & security of Ultra. This is his personal account of the operation.