Columbia subject headings:
Harvard subject headings:
Agriculture, Prehistoric--Congresses.
Antiquities, Prehistoric--Congresses
Excavations (Archaeology)--Norway--Congresses.
Farms--Germany--History--Congresses.
Farms--Iceland--History--Congresses.
Farms--Norway--History--Congresses.
Farms--Social aspects--Congresses.
Farms--Sweden--History--Congresses.
Iron age--Congresses.
Viking antiquities--Congresses.
Princeton subject headings:
Agriculture--Scandinavia--History--Congresses.
Scandinavia--Antiquities--Congresses.