Columbia subject headings:
Feudalism--Italy--Congresses.
Italy--Rural conditions--Congresses.
Nobility--Italy--History--Congresses.
Harvard subject headings:
Feudalism--Italy--Congresses.
Italy--Rural conditions--Congresses.
Nobility--Italy--History--Congresses.
Princeton subject headings:
Feudalism--Italy--Congresses.
Italy--Rural conditions--Congresses.
Nobility--Italy--History--Congresses.