Columbia subject headings:
Harvard subject headings:
German language--Acquisition.
German language--Pronunciation.
German language--Study and teaching--Foreign speakers.
Multilingualism--Germany.
Princeton subject headings:
German language--Pronunciation.
German language--Study and teaching--Chinese speakers.
German language--Study and teaching--Foreign speakers.
German language--Study and teaching--Polish speakers.
German language--Study and teaching--Russian speakers.