Columbia subject headings:
Harvard subject headings:
Cave churches--Italy, Southern.
Cave dwellings--Italy, Southern--History.
Italy, Southern--Antiquities.
Princeton subject headings:
Benedictines--Italy, Southern--History.
Cave monasteries--Italy, Southern--History.
Italy, Southern--Civilization.
Italy, Southern--History--535-1268.
Italy, Southern--Population.
Matera Region (Italy)--History.
Mottola Region (Italy)--History.