Columbia subject headings:
Building materials--Recycling--Italy--Trevi.
Church architecture--Italy--Trevi.
Trevi (Italy)--Antiquities.
Harvard subject headings:
Building materials--Recycling--Italy--Trevi.
Church architecture--Italy--Trevi.
Trevi (Italy)--Antiquities.
Princeton subject headings:
Building materials--Recycling--Italy--Trevi.
Church architecture--Italy--Trevi.
Trevi (Italy)--Antiquities.