Columbia subject headings:
Harvard subject headings:
Allegiance--Czechoslovakia--History--20th century--Congresses.
Allegiance--Germany (East)--History--20th century--Congresses.
Allegiance--Poland--History--20th century--Congresses.
Communism--Czechoslovakia--History--20th century--Congresses.
Communism--Germany (East)--History--20th century--Congresses.
Communism--Poland--History--20th century--Congresses.
Czechoslovakia--Politics and government--1945-1992--Congresses.
Germany (East)--Politics and government--Congresses.
Poland--Politics and government--1945-1980--Congresses.
Poland--Politics and government--1980-1989--Congresses.
Princeton subject headings:
Allegiance--Czechoslovakia--History--20th century--Congresses.
Allegiance--Germany (East)--History--20th century--Congresses.
Allegiance--Poland--History--20th century--Congresses.
Communism--Czechoslovakia--History--20th century--Congresses.
Communism--Germany (East)--History--20th century--Congresses.
Communism--Poland--History--20th century--Congresses.
Czechoslovakia--Politics and government--1945-1992--Congresses.
Germany (East)--Politics and government--Congresses.
Poland--Politics and government--1945-1980--Congresses.
Poland--Politics and government--1980-1989--Congresses.