Columbia subject headings:
Canada--Commercial policy--Congresses.
Interstate commerce--Canada--Congresses.
Non-tariff trade barriers--Canada--Congresses.
Harvard subject headings:
Canada--Commercial policy--Congresses.
Interstate commerce--Canada--Congresses.
Non-tariff trade barriers--Canada--Congresses.
Princeton subject headings:
Canada--Commercial policy--Congresses.
Non-tariff trade barriers--Canada--Congresses.