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Ayers, Frank (1964). Calculus. McGraw-Hill. ISBN 978-0-070-02653-7. ((cite book)): Invalid |ref=harv (help)
Berggren, Lennart; Borwein, Jonathan; Borwein, Peter (1997). Pi: a Source Book. Springer-Verlag. ISBN 978-0-387-20571-7. ((cite book)): Invalid |ref=harv (help)
Borwein, Jonathan; Borwein, Peter (1987). Pi and the AGM: a Study in Analytic Number Theory and Computational Complexity. Wiley. ISBN 978-0-471-31515-5. ((cite book)): Invalid |ref=harv (help)
Bronshteĭn, Ilia; Semendiaev, K. A. (1971). A Guide Book to Mathematics. H. Deutsch. ISBN 978-3-871-44095-3. ((cite book)): Invalid |ref=harv (help)
Eymard, Pierre; Lafon, Jean Pierre (1999). The Number Pi. American Mathematical Society. ISBN 978-0-8218-3246-2. ((cite book)): Invalid |ref=harv (help), English translation by Stephen Wilson.
Reitwiesner, George (1950). "An ENIAC Determination of pi and e to 2000 Decimal Places". Mathematical Tables and Other Aids to Computation. 4 (29): 11–15. doi:10.2307/2002695. ((cite journal)): Invalid |ref=harv (help)
Schepler, H. C. (1950). "The Chronology of Pi". Mathematics Magazine. 23 (3). Mathematical Association of America: 165–170 (Jan/Feb), 216–228 (Mar/Apr), and 279–283 (May/Jun). doi:10.2307/3029284. ((cite journal)): Invalid |ref=harv (help). issue 3 Jan/Feb, issue 4 Mar/Apr, issue 5 May/Jun
Blatner, David (1999). The Joy of Pi. Walker & Company. ISBN 978-0-8027-7562-7.
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Ramanujan, Srinivasa, "Modular Equations and Approximations to π", Quarterly Journal of Pure and Applied Mathematics, XLV, 1914, 350–372. Reprinted in G.H. Hardy, P.V. Seshu Aiyar, and B. M. Wilson (eds), Srinivasa Ramanujan: Collected Papers, 1927 (reprinted 2000), pp 23–29
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Viete, Francois, Variorum de Rebus Mathematicis Reponsorum Liber VII. F. Viete, Opera Mathematica (reprint), Georg Olms Verlag, 1970, pp 398–401, 436–446
Wagon, Stan, "Is Pi Normal?", The Mathematical Intelligencer, 7:3(1985) 65–67
Wallis, John, Arithmetica Infinitorum, sive Nova Methodus Inquirendi in Curvilineorum Quadratum, aliaque difficiliora Matheseos Problemata, Oxford 1655–6. Reprinted in vol. 1 (pp 357–478) of Opera Mathematica, Oxford 1693
Zebrowski, Ernest, A History of the Circle: Mathematical Reasoning and the Physical Universe, Rutgers Univ Press, 1999, ISBN 978-0-8135-2898-4
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