Columbia subject headings:
Harvard subject headings:
Enemies in literature--Congresses.
Enemies--Greece--History--To 1500--Congresses.
Friendship in literature--Congresses.
Friendship--Greece--History--To 1500--Congresses.
Princeton subject headings:
Enemies in literature--Congresses.
Enemies--Greece--History--To 1500--Congresses.
Friendship in literature--Congresses.
Friendship--Greece--History--To 1500--Congresses.