William F. Friedman NSA Archive - British Government Code and Cypher School Loyalty Declaration Made by Personnel Loyalty/Non-Disclosure Oath), 1941 - 4in1

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Files W.F.F. Archive Reports and Research Notes British Government Code and Cypher School Loyalty Declaration Made by Personnel Loyalty/Non-Disclosure Oath), 1941

Government Code and Cypher School Security Declaration

Document A72387