Columbia subject headings:
Harvard subject headings:
Asia--History
Ethnology--Eurasia
Europe--History.
Indo-European languages.
Indo-Europeans--Civilization.
Indo-Europeans--History.
Indo-Europeans--Origin.
Indo-Iranians--History.
Princeton subject headings:
Asia--Antiquities.
Europe--Antiquities.
Indo-European languages--History.
Indo-Europeans.
Prehistoric peoples--Asia.
Prehistoric peoples--Europe.