Columbia subject headings:
Metastasio, Pietro, 1698-1782.
Opera--Italy--17th century.
Opera--Italy--18th century.
Harvard subject headings:
Metastasio, Pietro, 1698-1782.
Opera--Italy--18th century
Opera--Italy--19th century
Princeton subject headings:
Metastasio, Pietro, 1698-1782--Criticism and interpretation.
Opera--Italy--17th century.
Opera--Italy--18th century.