Columbia subject headings:
Europe--Emigration and immigration--History--19th century.
Europe--Emigration and immigration--History--20th century.
Immigrants--United States--History--19th century.
Immigrants--United States--History--20th century.
United States--Emigration and immigration--History--19th century.
United States--Emigration and immigration--History--20th century.
Harvard subject headings:
Europe--Emigration and immigration--History--19th century.
Europe--Emigration and immigration--History--20th century.
Immigrants--United States--History--19th century
Immigrants--United States--History--20th century
United States--Emigration and immigration--History--19th century.
United States--Emigration and immigration--History--20th century.
Princeton subject headings:
Europe--Emigration and immigration--History.
United States--Emigration and immigration--History.