Columbia subject headings:
Düggelin, Werner--Interviews.
Düggelin, Werner.
Theatrical producers and directors--Switzerland--20th century--Biography.
Harvard subject headings:
Düggelin, Werner.
Theater--Switzerland--Basel.
Theater--Switzerland--Biography.
Theater--Switzerland--Zurich.
Princeton subject headings:
Düggelin, Werner--Interviews.
Düggelin, Werner.
Interviews.
Theatrical producers and directors--20th century--Switzerland--Biography.