Columbia subject headings:
Cities and towns--Germany--History--Congresses.
City planning--Germany--History--Congresses.
Middle class--Germany--History--Congresses.
Harvard subject headings:
Cities and towns--Europe--History--Congresses
Cities and towns--Germany--History--Congresses.
Europe--Court and courtiers--History--Congresses.
Germany--Court and courtiers--History--Congresses.
Princeton subject headings:
Cities and towns--Germany--History--Congresses.
City planning--Germany--History--Congresses.
Middle class--Germany--History--Congresses.