    listing below.
    </p>

    <p>
      The test integrals come from the <b>TEST_INT_2D</b> library.
    </p>

    <h3 align = "center">
      Usage:
    </h3>

    <p>
      <blockquote>
        <b>quadrature_test_2d</b> ( '<i>prefix</i>' )
      </blockquote>
      where
      <ul>
        <li>
          <i>prefix</i>, the common prefix for the files containing the abscissa (X),
          weight (W) and region (R) information of the quadrature rule;
        </li>
      </ul>
    </p>

    <p>
      If 