Columbia subject headings:
Canada--Commerce--United States.
Free trade--Political aspects--Canada.
Free trade--Political aspects--United States.
Softwood industry--Political aspects--Canada.
Softwood industry--Political aspects--United States.
United States--Commerce--Canada.
Harvard subject headings:
Princeton subject headings:
Canada--Commerce--United States.
Free trade--Political aspects--Canada.
Free trade--Political aspects--United States.
Softwood industry--Political aspects--Canada.
Softwood industry--Political aspects--United States.
United States--Commerce--Canada.