Columbia subject headings:
Emscher River Valley.
Internationale Bauausstellung Emscher Park GmbH.
Regional planning--Germany--Emscher River Valley.
Harvard subject headings:
Ems River Region (Germany)
Industries--Environmental aspects--Germany--Ems River Region.
Internationale Bauaustellung Emscher-Park.
Regional planning--Germany--Ems River Region.
Princeton subject headings: