Columbia subject headings:
Illinois--Description and travel.
Mississippi River Valley--Description and travel.
Missouri--Description and travel.
Ohio River Valley--Description and travel.
Harvard subject headings:
Illinois--Description and travel.
Mississippi River Valley--Description and travel.
Missouri--Description and travel.
Ohio River Valley--Description and travel.
Princeton subject headings:
Illinois--Description and travel.
Mississippi River Valley--Description and travel.
Missouri--Description and travel.
Ohio River Valley--Description and travel.