Secret days : code-breaking in Bletchley Park /
Briggs, Asa,1921-
London : Frontline Books,
c2011.
Includes bibliographical references and index.
Briggs, Asa, 1921-
Great Britain. Government Communications Headquarters
Great Britain. Government Code and Cypher School
Lorenz cipher system.
World War, 1939-1945
World War, 1939-1945
World War, 1939-1945
World War, 1939-1945