Columbia subject headings:
Indians of Mexico--Mexico--Tehuacán River Valley--Congresses.
Tehuacán River Valley (Mexico)--Antiquities--Congresses.
Tehuacán River Valley (Mexico)--History--Congresses.
Harvard subject headings:
Excavations (Archaeology)--Mexico--Tehuacán River Valley--Congresses.
Indians of Mexico--Mexico--Tehuacán River Valley--Congresses.
Tehuacán River Valley (Mexico)--Antiquities--Congresses.
Tehuacán River Valley (Mexico)--History--Congresses.
Princeton subject headings:
Indians of Mexico--Mexico--Tehuacán River Valley--Congresses.
Tehuacán River Valley (Mexico)--Antiquities--Congresses.
Tehuacán River Valley (Mexico)--History--Congresses.