Columbia subject headings:
Poland--Foreign relations--1945-
Poland--Politics and government--1945-1980.
Poland--Politics and government--1980-1989.
Harvard subject headings:
Poland--Foreign relations--1945-
Poland--Politics and government--1945-1980
Poland--Politics and government--1980-1989
Princeton subject headings:
Poland--Foreign relations--1945-
Poland--Politics and government--1945-1980.
Poland--Politics and government--1980-1989.