Columbia subject headings:
Basements--Europe--History--To 1500--Congresses.
Europe--Antiquities--Congresses.
Excavations (Archaeology)--Europe--Congresses.
Underground architecture--Europe--History--To 1500--Congresses.
Harvard subject headings:
Basements--Europe--History--To 1500--Congresses.
Europe--Antiquities--Congresses
Excavations (Archaeology)--Europe--Congresses
Underground architecture--Europe--History--To 1500--Congresses.
Princeton subject headings:
Basements--Europe--History--To 1500--Congresses.
Europe--Antiquities--Congresses.
Excavations (Archaeology)--Europe--Congresses.
Underground architecture--Europe--History--To 1500--Congresses.