Columbia subject headings:
Democracy--Germany--Congresses.
Germany--History--Unification, 1990--Congresses.
Harvard subject headings:
Democracy--Europe--Congresses
Democracy--Germany--Congresses.
Europe--Politics and government--1989---Congresses.
Germany--Politics and government--1990---Congresses.
Princeton subject headings:
Democracy--Germany--Congresses.
Germany--History--Unification, 1990--Congresses.