Columbia subject headings:
Harvard subject headings:
Germany (East)--Civilization--Congresses.
Germany (East)--Politics and government--Congresses.
Underground literature--Europe, Central--History and criticism--Congresses.
Underground literature--Germany (East)--History and criticism--Congresses.
Princeton subject headings:
Germany (East)--Civilization.
Germany (East)--Politics and government.
Underground literature--Germany (East)--History and criticism.