ISBN-13: 9780367708757 / Angielski / Twarda / 2021 / 144 str.
ISBN-13: 9780367708757 / Angielski / Twarda / 2021 / 144 str.
This book, first published in 1986 and an essential study of signals intelligence, examines Tsarist codebreakers and cryptanalysis during the Weimar Republic; the history of the Government Code and Cypher School; the Ultra programme; hand cyphers and wartime sigint; and surveillance under the Vichy regime.