Columbia subject headings:
Harvard subject headings:
Architecture, Modern--20th century--Germany--Berlin.
Architecture--Germany--Berlin
Architecture--Germany--Berlin--History.
Berlin (Germany)--Buildings, structures, etc.
Local transit stations--Germany--Berlin.
Local transit--Germany--Berlin--Design and construction.
Railroads, Elevated--Germany--Berlin--Design and construction.
Street-railroads--Germany--Berlin.
Subways--Germany--Berlin--Design and construction.
Princeton subject headings:
Street-railroads--Germany--Berlin.
Subways--Germany--Berlin.