d improvement to non-central chi squared distribution quantile due to
          Thomas Luu, <a href="http://discovery.ucl.ac.uk/1482128/" target="_top">Fast and accurate
          parallel computation of quantile functions for random number generation,
          Doctoral Thesis 2016</a>. <a href="http://discovery.ucl.ac.uk/1463470/" target="_top">Efficient
          and Accurate Parallel Inversion of the Gamma Distribution, Thomas Luu</a>
        </p>
<h5>
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