Columbia subject headings:
City planning--Germany--Cologne.
City planning--Germany--Frankfurt am Main.
Cologne (Germany)--Buildings, structures, etc.
Frankfurt am Main (Germany)--Buildings, structures, etc.
Harvard subject headings:
City planning--Germany--Cologne.
City planning--Germany--Frankfurt am Main
Cologne (Germany)--Buildings, structures, etc.
Frankfurt am Main (Germany)--Buildings, structures, etc.
Princeton subject headings:
City planning--Germany--Cologne.
City planning--Germany--Frankfurt am Main.
Cologne (Germany)--Buildings, structures, etc.
Frankfurt am Main (Germany)--Buildings, structures, etc.