Columbia subject headings:
Music--Italy--18th century--History and criticism--Congresses.
Music--Italy--19th century--History and criticism--Congresses.
Music--Italy--Spanish influences--Congresses.
Music--Spain--18th century--History and criticism--Congresses.
Music--Spain--19th century--History and criticism--Congresses.
Music--Spain--Italian influences--Congresses.
Opera--Italy--18th century--Congresses.
Opera--Italy--19th century--Congresses.
Opera--Spain--18th century--Congresses.
Opera--Spain--19th century--Congresses.
Harvard subject headings:
Music--Italy--18th century--History and criticism.
Music--Italy--19th century--History and criticism.
Music--Italy--Spanish influences.
Music--Spain--18th century--History and criticism.
Music--Spain--19th century--History and criticism.
Music--Spain--Italian influences.
Princeton subject headings:
Music--Italy--18th century--History and criticism--Congresses.
Music--Italy--19th century--History and criticism--Congresses.
Music--Italy--Spanish influences--Congresses.
Music--Spain--18th century--History and criticism--Congresses.
Music--Spain--19th century--History and criticism--Congresses.
Music--Spain--Italian influences--Congresses.
Opera--Italy--18th century--Congresses.
Opera--Italy--19th century--Congresses.
Opera--Spain--18th century--Congresses.
Opera--Spain--19th century--Congresses.