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3. Lucas N. H. Bunt, Phillip S. Jones, and Jack D. Bedient. The Historical Roots of Elementary Mathematics. Prentice-Hall, Englewood Cliffs, NJ, 1976.
4. A. B. Chace, and others. The Rhind Mathematical Papyrus. Math. Assoc. of America, Oberlin, OH, 1927–1929.
5. John H. Conway. On Numbers and Games, Academic Press, London, 1976.