Columbia subject headings:
Friesland (Netherlands)--Civilization.
Friesland (Netherlands)--History--Sources.
Hellema, Doeke Wijgers, 1766-1856.
Harvard subject headings:
Friesland (Netherlands)--Civilization.
Friesland (Netherlands)--History--Sources.
Hellema, Doeke Wijgers, 1766-1856.
Princeton subject headings: