Columbia subject headings:
Hesse (Germany)--Economic conditions--Congresses.
Regional planning--Germany--Hesse--Congresses.
Harvard subject headings:
Hesse (Germany)--Economic conditions--Congresses.
Regional planning--Germany--Hesse--Congresses.
Princeton subject headings:
Hesse (Germany)--Economic conditions--Congresses.
Regional planning--Germany--Hesse--Congresses.