Columbia subject headings:
Foreign workers, Mexican--United States.
Labor supply--Mexico.
Labor supply--United States.
Harvard subject headings:
Foreign workers, Mexican--United States.
International division of labor.
Mexico--Emigration and immigration.
Migrant labor--United States
Princeton subject headings:
Foreign workers, Mexican--United States.
International division of labor.
Mexico--Emigration and immigration.
Migrant labor--United States.