Columbia subject headings:
Harvard subject headings:
Architecture, Renaissance--Italy--History.
Architecture--Composition, proportion, etc.
Basilica di San Pietro in Vaticano.
Vatican City--Buildings, structures, etc.
Princeton subject headings:
Architecture, Renaissance--Italy--History.
Architecture--Composition, proportion, etc.
Basilica di San Pietro in Vaticano.
Vatican City--Buildings, structures, etc.