Calendar (1)

Mathematics (2)
Numbers
Quipu
 

Notes

1. Anthony Aveni. Empires of Time: Calendars, Clocks, and Cultures (Basic Books, Inc., 1989), 278-304.

2. John J. O'Conner and Edmund F. Robertson, "Mathematics of the Incas," http://turnbull.dcs.st-and.ac.uk/history/HistTopics/Inca_mathematics.html (School of Mathematics and Statistics, University of St. Andrews, Scotland, accessed 2004 Sep 6).