Columbia subject headings:
Regional planning--Germany--North Rhine-Westphalia.
Harvard subject headings:
Municipal government--Germany--North Rhine-Westphalia--History--20th century.
Municipal government--Germany--Rhine Province--History--20th century.
Regional planning--Germany--North Rhine-Westphalia--History--20th century.
Regional planning--Germany--Rhine Province--History--20th century.
Princeton subject headings:
Regional planning--Germany--North Rhine-Westphalia.