Columbia subject headings:
Communism.
Revolutions--Soviet Union.
Revolutions.
Soviet Union--History--Revolution, 1917-1921--Influence.
Soviet Union--Politics and government.
Harvard subject headings:
Communism.
Revolutions
Revolutions--Soviet Union.
Soviet Union--History--Revolution, 1917-1921--Influence.
Soviet Union--Politics and government.
Princeton subject headings: