Columbia subject headings:
Harvard subject headings:
Carolingians--Congresses.
Charles II, King of France, 823-877--Congresses.
Erigena, Johannes Scotus, approximately 810-approximately 877--Congresses.
Philosophy, Medieval--Congresses.
Princeton subject headings:
Carolingians--Intellectual life--Congresses.
Erigena, Johannes Scotus, approximately 810-approximately 877--Congresses.