Columbia subject headings:
Africa, West--Emigration and immigration--Maps.
European Union--Emigration and immigration--Maps.
Foreign workers--Europe, Western--Atlases.
Maps.
Harvard subject headings:
Africa, West--Emigration and immigration--Maps.
European Union countries--Emigration and immigration--Maps.
Princeton subject headings:
Africa, West--Emigration and immigration--Maps.
Europe--Emigration and immigration--Maps.