Columbia subject headings:
Europe, Central--Emigration and immigration--History.
United States--Emigration and immigration--History.
United States. Department of State--Records and correspondence.
Harvard subject headings:
Austria--Emigration and immigration.
Hungary--Emigration and immigration.
United States--Emigration and immigration.
Princeton subject headings:
Europe, Central--Emigration and immigration--History.
United States--Emigration and immigration--History.
United States. Department of State--Records and correspondence.