Columbia subject headings:
Berlin (Germany)--History--1945-1990.
Quadripartite Agreement on Berlin
World politics--1945-1989.
Harvard subject headings:
Berlin (Germany)--History--1945-1990
Berlin (Germany)--Politics and government--1945-1990
Quadripartite Agreement on Berlin
World politics--1945-
Princeton subject headings:
Berlin (Germany)--History--1945-1990.
Berlin (Germany)--Politics and government--1945-1990.
Quadripartite Agreement on Berlin
World politics--1945-1989.