Columbia subject headings:
Fillunger, Marie, 1850-1930--Correspondence.
Schumann, Eugenie, 1851-1938--Correspondence.
Singers--Austria--Correspondence.
Harvard subject headings:
Fillunger, Marie, 1850-1930--Correspondence.
Schumann, Eugenie, 1851-1938--Correspondence.
Sopranos (Singers)--Correspondence.
Princeton subject headings:
Fillunger, Marie, 1850-1930--Correspondence.
Schumann, Eugenie, 1851-1938--Correspondence.
Sopranos (Singers)--Correspondence.