iler</a>. Technical Report CSD TR 97 25, Dept. of
                Computer Science, Egham, Surrey, England, Dec. 20, 1997.
              </p>
            </td>
</tr>
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<td>
              <p>
                13.
              </p>
            </td>
<td>
              <p>
                Adrian Johnstone
              </p>
            </td>
<td>
              <p>
                <a href="http://www.cs.rhul.ac.uk/research/languages/projects/lookahead_backtrack.shtml" target="_top">Languages
                