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