Ifrah, G., & Bellos, D. (2005). Universal history of numbers: From prehistory to the invention of the computer v.2. Penguin.
Παραπομπή Chicago StyleIfrah, Georges, και David Bellos. Universal History of Numbers: From Prehistory to the Invention of the Computer V.2. New Delhi: Penguin, 2005.
Παραπομπή MLAIfrah, Georges, και David Bellos. Universal History of Numbers: From Prehistory to the Invention of the Computer V.2. Penguin, 2005.
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