Columbia subject headings:
Authors, German--20th century--Biography.
Hardt, Ernst, 1876-1947.
Theatrical producers and directors--Germany--Biography.
Harvard subject headings:
Authors, German--20th century--Biography
Hardt, Ernst, 1876-1947.
Theatrical producers and directors--Germany--Biography
Princeton subject headings:
Authors, German--20th century--Biography.
Hardt, Ernst, 1876-1947.
Theatrical producers and directors--Germany--Biography.