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