Columbia subject headings:
Dissenters--Soviet Union.
Political stability--Soviet Union.
Pressure groups--Soviet Union.
Soviet Union--Politics and government.
Harvard subject headings:
Dissenters--Soviet Union
Political stability--Soviet Union.
Pressure groups--Soviet Union.
Soviet Union--Politics and government--1917-1936.
Princeton subject headings:
Dissenters--Soviet Union.
Soviet Union--Politics and government--1953-.