diff --git a/bibtexbrowser.php b/bibtexbrowser.php
index d0cea4c..efaa318 100755
--- a/bibtexbrowser.php
+++ b/bibtexbrowser.php
@@ -1292,16 +1292,18 @@ class BibEntry {
    * URLs are replaced by HTML links.
    */
   function toEntryUnformatted() {
-    echo '<pre class="purebibtex">'; // pre is nice when it is embedded with no CSS available
-    $entry = $this->getFullText();
+    $result = "";
+    $result .= '<pre class="purebibtex">'; // pre is nice when it is embedded with no CSS available
+    $entry = str_replace('<','&lt;',$this->getFullText());
     if ($this->hasField('url')) {
       $url = $this->getField('url');
       // this is not a parsing but a simple replacement
       $entry = str_replace($url,'<a href="'.$url.'">'.$url.'</a>', $entry);
     }
 
-    echo $entry;
-    echo '</pre>';
+    $result .=  $entry;
+    $result .=  '</pre>';
+    return $result;
    }
 
    /**