title: What are the official XML reserved characters?
body: <p>In <a href="http://technet.microsoft.com/en-us/library/ms145315%28v=sql.90%29.aspx" rel="noreferrer">this page</a>, Microsoft says that XML reserved characters (and their entity) are the following ones:</p>
  
  <pre><code>&gt;    &amp;gt;
  &lt;    &amp;lt;
  &amp;    &amp;amp;
  %    &amp;#37;
  </code></pre>
  
  <p>But in <a href="http://weblogs.sqlteam.com/mladenp/archive/2008/10/21/Different-ways-how-to-escape-an-XML-string-in-C.aspx" rel="noreferrer">this other page</a>, I found that also <code>'</code> is a reserved character (and its entity is <code>&amp;apos;</code>).</p>
  
  <p>Can someone indicate me some official reference in which are listed all and only the XML reserved characters?</p>