Columbia subject headings:
Ethnicity--Congresses.
Foreign workers--United States--History--Congresses.
Immigrants--United States--History--Congresses.
Harvard subject headings:
Ethnicity--Congresses
Foreign workers--United States--History--Congresses.
Immigrants--United States--History--Congresses.
Princeton subject headings:
Ethnicity--United States--Congresses.
Foreign workers--United States--History--Congresses.
Immigrants--United States--History--Congresses.