Columbia subject headings:
Countertenors--Germany--Biography.
Countertenors--Interviews.
Kowalski, Jochen, 1954---Interviews.
Singers--Germany--Biography.
Singers--Germany--Interviews.
Harvard subject headings:
Countertenors--Germany--Biography.
Countertenors--Interviews.
Kowalski, Jochen, 1954---Interviews.
Singers--Germany--Biography
Singers--Germany--Interviews.
Princeton subject headings:
Countertenors--Interviews.
Interviews.
Kowalski, Jochen, 1954---Interviews.