Columbia subject headings:
Harvard subject headings:
Opposition (Political science)--Germany (East)--History--20th century--Congresses.
Political parties--Germany (East)--History--20th century--Congresses.
Revolutionaries--Germany (East)--History--20th century--Congresses.
Sozialistische Einheitspartei Deutschlands--History--20th century--Congresses.
Princeton subject headings:
Germany (West)--Emigration and immigration--Congresses.
Nineteen eighties--Congresses.
Opposition (Political science)--Germany (East)--Congresses.
Political persecution--Germany (East)--Congresses.
Political refugees--Germany (East)--Congresses.
Political refugees--Germany (West)--Congresses.