Columbia subject headings:
Architecture, Romanesque--Germany--Cologne.
Church architecture--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
Harvard subject headings:
Architecture, Romanesque--Germany--Cologne.
Church architecture--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
Princeton subject headings:
Architecture, Romanesque--Germany (West)--Cologne.
Church architecture--Germany (West)--Cologne.
Cologne (Germany)--Buildings, structures, etc.