Columbia subject headings:
Cathedrals--Germany--Cologne.
Cologne (Germany)--Buildings, structures, etc.
Kölner Dom.
Harvard subject headings:
Cologne (Germany)--Antiquities.
Cologne (Germany)--Buildings, structures, etc.
Excavations (Archaeology)--Germany--Cologne.
Kölner Dom--History.
Princeton subject headings:
Cologne (Germany)--Antiquities.
Cologne (Germany)--Buildings, structures, etc.
Excavations (Archaeology)--Germany (West)--Cologne.
Kölner Dom--History.