Columbia subject headings:
Harvard subject headings:
Civilization, Medieval--Congresses
Estonia--Church history--Congresses.
Estonia--History--To 1500--Congresses.
Estonia--Languages--History--Congresses.
Estonia--Social conditions--To 1500--Congresses.
Livonia--History--To 1500--Congresses.
Livonia--Social conditions--To 1500--Congresses.
Princeton subject headings:
Estonia--Church history.
Estonia--History--To 1500.
Estonia--Rural conditions.
Estonia--Social conditions--To 1500.
Livonia--History--To 1500.
Livonia--Rural conditions.
Livonia--Social conditions--To 1500.