Columbia subject headings:
Agriculture--Europe--History--Congresses.
Europe--Rural conditions--Congresses.
Land tenure--Europe--History--Congresses.
Harvard subject headings:
Agriculture--Europe--History--Congresses.
Europe--Rural conditions--Congresses
Land tenure--Europe--History--Congresses.
Princeton subject headings:
Agriculture--Europe--History--Congresses.
Europe--Rural conditions--Congresses.
Land tenure--Europe--History--Congresses.