Columbia subject headings:
Espionage--Great Britain.
Intelligence service--Soviet Union.
Lonsdale, Gordon Arnold, 1924-1970.
Spies--Great Britain.
Harvard subject headings:
Espionage--Great Britain.
Intelligence service--Soviet Union.
Lonsdale, Gordon Arnold, 1924-
Spies--Great Britain.
Princeton subject headings:
Espionage.
Intelligence service.