Reference:

[1] https://en.wikipedia.org/wiki/Binomial_proportion_confidence_interval
[2] Keith Dunnigan.2008. Confidence Interval Calculation for Binomial Proportions.
[3] Stein Vollset. “Confidence Intervals For a Binomial Proportion” Statistics in Medicine, Vol 12, pp 809-824, 1993.
[4] Newcombe RG. Two-sided confidence intervals for the single proportion: comparison of seven methods. Stat Med. 1998;17(8):857-872.
[5] K. Krishnamoorthy and Jie Peng. “Some Properties of the Exact and Score Methods for Binomial Proportion and Sample Size Calculation” Communications in Statistics – Simulation and Computation, 36: pp 1171-1186, 2007.