ration Using Sparse Grids,<br>
          Numerical Algorithms,<br>
          Volume 18, Number 3-4, 1998, pages 209-232.
        </li>
        <li>
          Gene Golub, John Welsch,<br>
          Calculation of Gaussian Quadrature Rules,<br>
          Mathematics of Computation,<br>
          Volume 23, Number 106, April 1969, pages 221-230.
        </li>
        <li>
          Prem Kythe, Michael Schaeferkotter,<br>
          Handbook of Computational Methods for Integration,<br>
          Chapman and Hal