Columbia subject headings:
Harvard subject headings:
Civilization--Congresses
Gnosticism--Congresses
Hellenism--Congresses
Princeton subject headings:
Christianity--Origin--Congresses.
Dualism--Congresses.
Egypt--Religion--Congresses.
Gnosticism--Congresses.
Monasticism and religious orders--Congresses.
Nag Hammadi codices--Congresses.