Columbia subject headings:
Mexico--Emigration and immigration.
Mexico--Relations--United States.
North America--Economic integration.
United States--Emigration and immigration.
United States--Relations--Mexico.
Harvard subject headings:
Mexican-American Border Region--Economic integration--Congresses.
Mexico--Foreign economic relations--United States--Congresses.
United States--Foreign economic relations--Mexico--Congresses.
Princeton subject headings: