Columbia subject headings:
Harvard subject headings:
Church architecture--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
St. Gereon (Church : Cologne, Germany)
Princeton subject headings:
Church architecture--Germany--Cologne.
Church buildings--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
Excavations (Archaeology)--Germany--Cologne.
St. Gereon (Church : Cologne, Germany)