title: How to make geometry topology via XML and XSD?
body: <p>I need to find the way of defining lines using topology representation.
  Now i have something similar to it:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;Root&gt;
      &lt;Points&gt;
          &lt;Point&gt;
              &lt;UIDP&gt;1&lt;/UIDP&gt;
              &lt;X&gt;5379847.689&lt;/X&gt;
              &lt;Y&gt;1223602.644&lt;/Y&gt;
              &lt;MX&gt;0.05&lt;/MX&gt;
              &lt;MY&gt;0.05&lt;/MY&gt;
          &lt;/Point&gt;
          &lt;Point&gt;
              &lt;UIDP&gt;2&lt;/UIDP&gt;
              &lt;X&gt;5379828.473&lt;/X&gt;
              &lt;Y&gt;1223606.113&lt;/Y&gt;
              &lt;MX&gt;0.05&lt;/MX&gt;
              &lt;MY&gt;0.05&lt;/MY&gt;
          &lt;/Point&gt;
      &lt;/Points&gt;
      &lt;Lines&gt;
          &lt;Line&gt;
              &lt;Point&gt;1&lt;/Point&gt;/&gt;
              &lt;Point&gt;2&lt;/Point&gt;/&gt;
          &lt;/Line&gt;
      &lt;/Lines&gt;  
  &lt;/Root&gt;
  </code></pre>
  
  <p>Where Line/Point is the value of point unique id(UIDP).</p>
  
  <p><strong>Questions</strong></p>
  
  <ol>
  <li>Is there any way to make it more clearly, get not only ID but hole
  point definition using references or something similar?</li>
  <li>How to make it using XLink or XPointer?</li>
  <li>How to define it in XSD Schema 1.1?</li>
  </ol>