Columbia subject headings:
Andes Region--Antiquities.
Inca astronomy.
Inca calendar.
Incas--Antiquities.
Harvard subject headings:
Andes Region--Antiquities.
Inca astronomy--Congresses.
Incas--Calendar--Congresses.
Princeton subject headings:
Archaeoastronomy--Peru.
Inca astronomy.
Incas--Calendar.
Indians of South America--Andes Region--Astronomy.
Indians of South America--Andes Region--Calendar.