Columbia subject headings:
Agriculture--Canada.
Agriculture--United States.
Canada--Description and travel.
United States--Description and travel.
Harvard subject headings:
Agriculture--Canada.
Agriculture--United States
Canada--Description and travel.
United States--Description and travel.
Princeton subject headings:
Agriculture--United States.
Canada--Description and travel--Early works to 1800.
Canada--Description and travel.
Canada. Agriculture Canada
United States--Description and travel.