Radiocarbon calibration curve spanning 0 to 50,000 years BP based on paired Th-230/U-234/U-238 and C-14 dates on pristine corals, Fairbanks, R. G.; Mortlock, R. A.; Chiu, T. C.; Cao, L.; Kaplan, A.; Guilderson, T. P.; Fairbanks, T. W.; Bloom, A. L.; Grootes, P. M.; Nadeau, M. J. , Quaternary Science Reviews, Sep, Volume 24, Issue 16-17, p.1781-1796, (2005), DOI 10.1016/j.quascirev.2005.04.007 Abstract