Columbia subject headings:
Composers--Correspondence.
Wolf-Ferrari, Ermanno, 1876-1948.
Harvard subject headings:
Composers--Correspondence
Wolf-Ferrari, Ermanno, 1876-1948--Correspondence.
Wolf-Ferrari, Ermanno, 1876-1948.
Princeton subject headings:
Composers--Correspondence.
Wolf-Ferrari, Ermanno, 1876-1948.