Columbia subject headings:
China--Politics and government--1949-1976.
China--Politics and government--1976-2002.
Soviet Union--Politics and government--1945-1991.
Harvard subject headings:
China--Politics and government--1949-
Soviet Union--Politics and government--1945-1991.
Princeton subject headings:
China--Politics and government--1949-
Soviet Union--Politics and government--1945-1991.