Columbia subject headings:
Espionage, Soviet.
Soviet Union. Komitet gosudarstvennoĭ bezopasnosti.
Spies--Soviet Union.
Harvard subject headings:
Espionage, Soviet.
Soviet Union. Komitet gosudarstvennoĭ bezopasnosti.
Spies--Soviet Union.
Princeton subject headings:
Espionage, Soviet.
Soviet Union. Komitet gosudarstvennoĭ bezopasnosti
Spies--Soviet Union.