Columbia subject headings:
Harvard subject headings:
Europe--Emigration and immigration--Congresses.
Immigrants--Cultural assimilation--Europe--Congresses.
Immigrants--Cultural assimilation--Portugal--Congresses.
Portugal--Emigration and immigration--Congresses.
Princeton subject headings:
Europe--Emigration and immigration--Congresses.
Immigrants--Cultural assimilation--Europe--Congresses.
Immigrants--Cultural assimilation--Portugal--Congresses.
Portugal--Emigration and immigration--Congresses.