Effects Bounce Issue. - .stop()?

Effects Bounce Issue. - .stop()?

Hi all.
I am trying to stop this script from continually running whilst to mouse is over the link.
I have tried using '.stop()', but to no avail. Perhaps i'm putting in the wrong place?

I would like the script to run just the once whilst the mouse is over the link.
Also, is their a way to stop the script 'cuing', if the mouse were to pass over the link a few times?

Can anyone offer advice on this?

All input will be greatly received.

Many thanks,
Bil

<script src="http://jqueryui.com/latest/ui/effects.core.js"></script>
<script src="http://jqueryui.com/latest/ui/effects.bounce.js"></script>

<script type="text/javascript">
  $(document).ready(function(){
   
$("li").mouseenter(function () {
      $(this).effect("bounce", { times:0 }, 100);
});

  });
  </script>