Columbia subject headings:
Harvard subject headings:
German language--Grammar.
German language--Research.
German language--Study and teaching--Foreign speakers.
German language--Usage.
German language--Variation.
Stickel, Gerhard.
Princeton subject headings:
German language--Grammar.
German language--Research.
German language--Study and teaching--Foreign speakers.
German language--Usage.
German language--Variation.
Stickel, Gerhard.