Columbia subject headings:
Bilingualism--Congresses.
German language--Social aspects--Congresses.
German language--Study and teaching--Foreign speakers--Congresses.
Languages in contact--Congresses.
Harvard subject headings:
Bilingualism--Congresses
German language--Social aspects--Congresses.
German language--Study and teaching--Foreign speakers--Congresses.
Languages in contact--Congresses.
Princeton subject headings:
Bilingualism--Congresses.
German language--Social aspects--Congresses.
German language--Study and teaching--Foreign speakers--Congresses.
Germany--Foreign population--Congresses.
Languages in contact--Congresses.