Columbia subject headings:
Slavery--Greece--History--Congresses.
Slavery--Rome--History--Congresses.
Harvard subject headings:
Slavery--Greece--History--Congresses.
Slavery--Rome--History--Congresses.
Princeton subject headings:
Excavations (Archaeology)--Greece--Congresses.
Excavations (Archaeology)--Rome--Congresses.
Greece--Antiquities--Congresses.
Rome--Antiquities--Congresses.
Slavery--Greece--Congresses.
Slavery--Research--Congresses.
Slavery--Rome--Congresses.