Columbia subject headings:
Architects--Germany.
Architecture--Germany--History--20th century.
Betz Architekten.
Betz, Walther.
Harvard subject headings:
Architects--Germany
Architecture, Modern--20th century--Germany.
Betz Architekten.
Betz, Walther.
Princeton subject headings:
Architectural firms--Germany.
Architecture, Modern--20th century--Germany.
Betz Architekten.
Betz, Walther, 1929-2010.