Columbia subject headings:
Fur trade--Great Plains--History--Sources.
Great Plains--Discovery and exploration--Canadian.
Hidatsa Indians--History--Sources.
Indians of North America--Great Plains--History--Sources.
Mandan Indians--History--Sources.
Harvard subject headings:
Fur trade--Great Plains--History--Sources.
Great Plains--Discovery and exploration--Canadian.
Hidatsa Indians--History--Sources.
Indians of North America--Great Plains--History--Sources.
Mandan Indians--History--Sources.
Princeton subject headings:
Fur trade--Great Plains--History--Sources.
Great Plains--Discovery and exploration--Canadian.
Hidatsa Indians--History--Sources.
Indians of North America--Great Plains--History--Sources.
Mandan Indians--History--Sources.