Columbia subject headings:
Feudalism--Germany--Harz Mountains Region--History--Sources.
Harz Mountains Region (Germany)--History--Sources.
Heinrich I, Graf von Regenstein, -approximately 1241.
Harvard subject headings:
Feudalism--Germany--Harz Mountains Region--History--Sources.
Harz Mountains Region (Germany)--History--Sources.
Heinrich I, Graf von Regenstein, -approximately 1241.
Princeton subject headings:
Feudalism--Germany--Halberstadt Region--History--Sources.
Halberstadt Region (Germany)--History--Sources.
Heinrich I, Graf von Regenstein, -approximately 1241.
Nobility--Germany--Halberstadt Region--History--Sources.