Columbia subject headings:
Germany (East)--Foreign relations.
Germany (East)--Relations--Poland.
Poland--Relations--Germany (East)
Harvard subject headings:
Europe, Eastern--Foreign relations--1945-1989.
Germany--Foreign relations--Europe, Eastern.
Germany--Foreign relations--Poland.
Poland--Foreign relations--Germany
Princeton subject headings:
Europe, Eastern--Foreign relations--1945-1989.
Germany--Foreign relations--Europe, Eastern.
Germany--Foreign relations--Poland.
Poland--Foreign relations--Germany.