       the weights of a 1D Clenshaw Curtis rule of order 3.
        </li>
        <li>
          <a href = "cc_d1_o3_r.txt">
          cc_d1_o3_r.txt</a>,
          defines the range of the region.
        </li>
      </ul>
    </p>

    <p>
      The second factor is a 1D Gauss Legendre rule of order 2:
      <ul>
        <li>
          <a href = "gl_d1_o2_x.txt">
          gl_d1_o2_x.txt</a>,
          the abscissas of a 1D Clenshaw Curtis rule of order 2.
        </li>
        <li>
          <a href = "g