Columbia subject headings:
Missouri--Description and travel.
United States--Description and travel.
Harvard subject headings:
Duden, Gottfried--Travel--Missouri.
Duden, Gottfried--Travel--United States.
Missouri--Description and travel.
United States--Description and travel.
West (U.S.)--Description and travel.
Princeton subject headings:
Duden, Gottfried.
Missouri--Description and travel.
United States--Description and travel.