Columbia subject headings:
Canada--Emigration and immigration--Congresses.
Citizenship--Canada--Congresses.
Citizenship--Europe--Congresses.
Citizenship--United States--Congresses.
Europe--Emigration and immigration--Congresses.
Naturalization--Canada--Congresses.
Naturalization--Europe--Congresses.
Naturalization--United States--Congresses.
United States--Emigration and immigration--Congresses.
Harvard subject headings:
Canada--Emigration and immigration--Congresses.
Citizenship--Canada--Congresses.
Citizenship--Europe--Congresses.
Citizenship--United States--Congresses.
Europe--Emigration and immigration--Congresses.
Naturalization--Canada--Congresses.
Naturalization--Europe--Congresses.
Naturalization--United States--Congresses.
United States--Emigration and immigration--Congresses.
Princeton subject headings:
Canada--Emigration and immigration--Congresses.
Citizenship--Canada--Congresses.
Citizenship--Europe--Congresses.
Citizenship--United States--Congresses.
Europe--Emigration and immigration--Congresses.
Naturalization--Canada--Congresses.
Naturalization--Europe--Congresses.
Naturalization--United States--Congresses.
United States--Emigration and immigration--Congresses.