Columbia subject headings:
Excavations (Archaeology)--Netherlands--Friesland.
Friesland (Netherlands)--Antiquities.
Friesland (Netherlands)--Economic conditions.
Harvard subject headings:
Excavations (Archaeology)--Netherlands--Friesland.
Friesland (Netherlands)--Antiquities.
Friesland (Netherlands)--Economic conditions.
Princeton subject headings:
Economic history--Netherlands--Friesland.
Excavations (Archaeology)--Netherlands--Friesland.
Friesland (Netherlands)--Antiquities.
Friesland (Netherlands)--Economic conditions.