Columbia subject headings:
Harvard subject headings:
Archaeology, Medieval.
Excavations (Archaeology)--Germany--Oldenburg Region.
Fortification--Germany--Oldenburg Region.
Oldenburg Region (Germany)--Antiquities, Slavic.
Slavs--Germany--Oldenburg Region--History.
Princeton subject headings:
Germany--Antiquities, Slavic.
Oldenburg Region (Germany)--History.
Slaves--Germany--Oldenburg Region.