Columbia subject headings:
Harvard subject headings:
Germany--Emigration and immigration--Government policy.
Immigrants--Government policy--Germany--History--20th century.
Immigrants--Government policy--Germany--History--21st century.
Princeton subject headings:
Germany--Emigration and immigration--Government policy.
Immigrants--Government policy--Germany--History--20th century.
Immigrants--Government policy--Germany--History--21st century.