Columbia subject headings:
Czechoslovakia--Politics and government--1968-1989.
Germany (East)--Politics and government.
Harvard subject headings:
Czechoslovakia--Politics and government--1968-1989.
Czechoslovakia--Politics and government--1989-
Germany (East)--Politics and government.
Princeton subject headings:
Czechoslovakia--History--Intervention, 1968.
Germany (East)--Politics and government.