Columbia subject headings:
Grubenhagen (Principality)--History.
Osterode am Harz (Germany)--History.
Harvard subject headings:
Grubenhagen (Principality)--History.
Osterode am Harz (Germany)--History.
Princeton subject headings:
Grubenhagen (Principality)--History--Sources.
Osterode am Harz (Germany : Kreis)--History--Sources.
Osterode am Harz (Germany)--History--Sources.