<?php
$url="http://feeds.feedburner.com/gianniamato";
  $doc = new DOMDocument;
   if(!is_file('rss.xml') OR (is_file('rss.xml') && (time() > filemtime('rss.xml')+28800))){
    $doc->formatOutput = true;
    $doc->load($url);
    $doc->save('rss.xml');
   }

  $doc->load('rss.xml');
  $xpath = new DOMXPath($doc);
  $xpath->registerNameSpace('atom', 'http://www.w3.org/2005/Atom');

?>
<ul>
<?php
  $nodo = $xpath->query('//atom:entry');
    $a = 0;
    foreach ($nodo as $nodo){
       $title = $nodo->getElementsByTagName('title')->item(0)->nodeValue;
       $link =  $nodo->getElementsByTagName('link')->item(0)->nodeValue;
       echo "<li><a href=\"".$link."\" target=\"_blank\">".$title."</a></li>
";
  }
?>
</ul>