Columbia subject headings:
Architecture--Germany--Essen--History--20th century.
Ingenhoven Overdiek und Partner.
Rheinisch-Westfälisches Elektrizitätswerk Aktiengesellschaft--Buildings.
Tall buildings--Germany--Essen.
Harvard subject headings:
Architecture, Modern--20th century--Germany--Essen.
Architecture--Germany--Essen--History--20th century.
Architecture--Germany--Essen--History.
Essen (Germany)--Buildings, structures, etc.
Ingenhoven Overdiek und Partner.
Rheinisch-Westfälisches Elektrizitätswerk Aktiengesellschaft--Buildings.
Tall buildings--Design and construction
Tall buildings--Environmental aspects.
Tall buildings--Germany--Essen.
Princeton subject headings:
Architecture, Modern--20th century--Germany--Essen.
Essen (Germany)--Buildings, structures, etc.
Ingenhoven Overdiek und Partner.
Tall buildings--Design and construction.
Tall buildings--Environmental aspects.
Tall buildings--Germany--Essen.