Columbia subject headings:
Basilica di San Pietro in Vaticano. Cupola.
Harvard subject headings:
Basilica di San Pietro in Vaticano--Cupola.
Church buildings--Vatican City
Domes--Italy--Rome.
Domes--Vatican City.
Rome (Italy)--Buildings, structures, etc.
Princeton subject headings:
Basilica di San Pietro in Vaticano. Cupola.