References
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Moultrie TA, RE Dorrington, AG Hill, KH Hill, IM Timæus and B Zaba (2012). Tools for Demographic Estimation. Paris: International Union for the Scientific Study of Population.
demographicestimation.iussp.org
United Nations (2001). Principles and Recommendations for a Vital Statistics System Revision 2. New York: United Nations. http://unstats.un.org/unsd/publication/SeriesM/SeriesM_19rev2E.pdf .