Columbia subject headings:
Defense information, Classified--Russia (Federation)
Information technology--Security measures--Russia (Federation)
Official secrets--Russia (Federation)
Harvard subject headings:
Defense information, Classified--Russia (Federation)
Information technology--Security measures--Russia (Federation)
Official secrets--Russia (Federation)
Princeton subject headings:
Cryptographers--Russia (Federation)--Correspondence.
Cryptography--History.
Stealth technology.
World War, 1939-1945--Cryptography.