Columbia subject headings:
Interstate commerce--Canada.
Non-tariff trade barriers--Canada--Provinces.
Trade regulation--Canada--Provinces.
Harvard subject headings:
Interstate commerce--Canada.
Non-tariff trade barriers--Canada--Provinces.
Non-tariff trade barriers--Canada.
Restraint of trade--Canada.
Trade regulation--Canada
Trade regulation--Canada--Provinces.
Princeton subject headings:
Interstate commerce--Canada.
Non-tariff trade barriers--Canada--Provinces.
Trade regulation--Canada--Provinces.