Columbia subject headings:
European Union countries--Boundaries.
Illegal immigration--European Union countries.
Noncitizens--European Union countries.
Refugee camps--European Union countries.
Refugees--European Union countries.
Harvard subject headings:
European Union countries--Boundaries.
Illegal immigration--European Union countries.
Noncitizens--European Union countries
Refugee camps--European Union countries.
Refugees--European Union countries.
Princeton subject headings: