Columbia subject headings:
Music--Italy--Spanish influences.
Musical theater--Spain--Italian influences.
Opera--Italy--19th century.
Opera--Spain--19th century.
Verdi, Giuseppe, 1813-1901--Appreciation--Spain.
Harvard subject headings:
Verdi, Giuseppe, 1813-1901--Criticism and interpretation.
Verdi, Giuseppe, 1813-1901--Spanish influences.
Princeton subject headings: