<tt>| ?- query 0.</tt>
  <li>The description of the <a href="traffic/traffic">Traffic World</a>
      and Test Scenarios <a href="traffic/scenario1">1</a>,
      <a href="traffic/scenario2">2</a> and
      <a href="traffic/scenario3">3</a><br>
      To run Test 1, type<br>
      <tt>| ?- loadf scenario1.</tt><br>
      and then<br>
      <tt>| ?- query 1.</tt><br>
      or<br>
      <tt>| ?- query 2.</tt>
</ul>
 <li> From the paper
"<a href="http://www.cs.utexas.edu/users/vl/papers/airport.ps">Getting to th