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<blockquote class="gmail_quote" style="PADDING-LEFT: 1ex; MARGIN: 0px 0px 0px 0.8ex; BORDER-LEFT: #ccc 1px solid">  Doesn't answer your question, but a helpful link no the less:</blockquote>
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<div><a href="http://www.mindspring.com/~clist/PotGraph.html">http://www.mindspring.com/~clist/PotGraph.html</a></div>
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<div>peng</div><br> </div><br>