Columbia subject headings:
German language--History.
Mehl, Erwin, 1890-1984.
Tekusch, Karl, 1890-1977.
Harvard subject headings:
German language--Austria--Vienna--Societies, etc.--History.
German language--History
Mehl, Erwin, 1890-1984
Tekusch, Karl, 1890-1977
Verein Muttersprache--History.
Princeton subject headings:
German language--History.
Mehl, Erwin, 1890-1984.
Tekusch, Karl, 1890-1977.