Columbia subject headings:
Land tenure--History--Congresses.
Real property--History--Congresses.
Harvard subject headings:
Europe--History--392-814--Congresses.
Land tenure--History--Congresses.
Real property--History--Congresses.
Princeton subject headings:
Administration of estates--Europe--History--Congresses.
Farms, Large--Europe--History--Congresses.
Feudalism--Europe--History--Congresses.
Land tenure--Europe--History--Congresses.
Manors--Europe--History--Congresses.