Columbia subject headings:
Aztecs.
Indian calendar--Mexico.
Indians of Mexico--Antiquities.
Mexico--History--Conquest, 1519-1540.
Natural history--Mexico.
Harvard subject headings:
Aztecs.
Indians of Mexico--Antiquities
Mexico--Antiquities.
Mexico--History--Conquest, 1519-1540.
Natural history--Mexico
Princeton subject headings:
Aztecs--History--16th century--sources.
Indians of Mexico--Antiquities--Sources.
Indians of Mexico--Calendar--History--Sources.
Mexico--History--Conquest, 1519-1540--Sources.
Natural history--Mexico--Sources.