Columbia subject headings:
Harvard subject headings:
Communism--Europe, Eastern--History--20th century--Congresses.
Communist countries--Economic conditions--20th century.
Communist countries--Politics and government--20th century.
Communist countries--Social conditions--20th century.
Europe, Eastern--History--1945-1989--Congresses.
Socialism--Europe, Eastern--History--20th century--Congresses.
Princeton subject headings:
Communism--Europe, Eastern--History--20th century--Congresses.
Communist countries--Economic conditions--20th century.
Communist countries--Politics and government--20th century.
Communist countries--Social conditions--20th century.
Europe, Eastern--History--1945-1989--Congresses.
Socialism--Europe, Eastern--History--20th century--Congresses.