Columbia subject headings:
Foreign workers, Mexican--United States.
Mexicans--Employment--United States.
Mexico--Emigration and immigration.
United States--Emigration and immigration.
Harvard subject headings:
Foreign workers, Mexican--United States.
Mexicans--Employment--United States.
Mexico--Emigration and immigration.
United States--Emigration and immigration.
Princeton subject headings:
Foreign workers, Mexican--United States.
Mexicans--Employment--United States.
Mexico--Emigration and immigration.
United States--Emigration and immigration.