Columbia subject headings:
Emigration and immigration law--United States--Congresses.
Foreign workers--United States--Congresses.
Migrant agricultural laborers--Legal status, laws, etc.--United States--Congresses.
Harvard subject headings:
Emigration and immigration law--United States--Congresses.
Foreign workers--United States--Congresses.
Migrant agricultural laborers--Legal status, laws, etc.--United States--Congresses.
Princeton subject headings: