 first four
      node indices are the same as for the linear tet mesh.  The next six
      node indices may be thought of as being obtained as averages of
      pairs of the first four nodes.  Symbolically, this may be thought of as:
      <pre>
        1  2  3  4 (1+2) (1+3) (1+4) (2+3) (2+4) (3+4)
      </pre>
    </p>

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

    <p>
      The computer code and data files described and made available on this web page
      are distributed under
      <a hre