1. Premack D., Premack A., Original Intelligence (McGraw-Hill, New York, 2003).
2. Coe M. D., Breaking the Maya Code (Thames & Hudson, London, 1999).
3. Ascher M., Ascher R., Code of the Quipi: A Study in Media, Mathematics, and Culture (Univ. of Michigan, Ann Arbor, MI, 1981).
4. On mathematics in the history of Sub-Saharan Africa
5. Li Y., Ran Du S., Chinese Mathematics, a Concise History, , Grossly J. N., Lun A. W. C., Eds. (Clarendon Press, Oxford, UK, 1987).