Columbia subject headings:
Communism--Soviet Union.
Obshchestvo byvsh. politicheskikh katorzhan i ss.-poselent︠s︡ev (Soviet Union)
Political crimes and offenses--Soviet Union.
Harvard subject headings:
Exiles--Soviet Union--History.
Forced labor--Soviet Union--History
Labor movement--Soviet Union--History.
Political prisoners--Soviet Union--History.
Revolutions--Soviet Union--History.
Soviet Union--History--Revolution, 1917-1921.
Soviet Union--Politics and government.
Working class--Political activity--Soviet Union.
Princeton subject headings:
Communism--Soviet Union.
Obshchestvo byvsh. politicheskikh katorzhan i ss.-poselent︠s︡ev (Soviet Union)
Political crimes and offenses--Soviet Union.