   the source code.
        </li>
      </ul>
    </p>

    <h3 align = "center">
      Examples and Tests:
    </h3>

    <p>
      As an example, we make a 2D product rule.
    </p>

    <p>
      The first factor is a 1D Clenshaw Curtis rule of order 3:
      <ul>
        <li>
          <a href = "cc_d1_o3_x.txt">
          cc_d1_o3_x.txt</a>,
          the abscissas of a 1D Clenshaw Curtis rule of order 3.
        </li>
        <li>
          <a href = "cc_d1_o3_w.txt">
          cc_d1_o3_w.txt</a>,
   