Columbia subject headings:
Architecture--Italy--Iblei Mountains Region.
Dry stone walls--Italy--Iblei Mountains Region.
Vernacular architecture--Italy--Iblei Mountains Region.
Harvard subject headings:
Architecture--Italy--Iblei Mountains Region.
Dry stone walls--Italy--Iblei Mountains Region.
Vernacular architecture--Italy--Iblei Mountains Region.
Princeton subject headings:
Architecture--Italy--Iblei Mountains Region.
Dry stone walls--Italy--Iblei Mountains Region.
Vernacular architecture--Italy--Iblei Mountains Region.