Columbia subject headings:
Celts--Italy--Po River Valley.
Etruscans--Italy--Po River Valley.
Po River Valley (Italy)--Antiquities.
Po River Valley (Italy)--Civilization.
Harvard subject headings:
Celts--Italy--Po River Valley.
Etruscans--Italy--Po River Valley.
Po River Valley (Italy)--History.
Princeton subject headings:
Celts--Italy--Po Valley.
Etruscans--Italy--Po Valley.
Po River Valley (Italy)--Antiquities.
Po River Valley (Italy)--Civilization.