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2. Nice Cubic Polynomials for Curve Sketching
3. H. Davenport,The Higher Arithmetic, 5th edition, Cambridge University Press, London, 1982.
4. Leonard E. Dickson,History of the Theory of Numbers, Vol. 2, Chelsea Publishing Co., 1952.
5. Leonard E. Dickson,Introduction to the Theory of Numbers, Dover Publications, Inc., New York, 1957.