Columbia subject headings:
Harvard subject headings:
Agricultural laborers--Australia.
Agricultural laborers--Canada.
Agricultural laborers--United States
Migrant agricultural laborers--Australia.
Migrant agricultural laborers--Canada.
Migrant agricultural laborers--United States.
Princeton subject headings:
Agricultural laborers--Australia--Congresses.
Agricultural laborers--Canada--Congresses.
Agricultural laborers--United States--Congresses.
Seasonal labor--Australia--Congresses.
Seasonal labor--Canada--Congresses.
Seasonal labor--United States--Congresses.