diff --git a/book.php b/book.php
index 3a9a071..ae49e4c 100644
--- a/book.php
+++ b/book.php
@@ -154,6 +154,17 @@ class Book extends Base {
         }
     }
     
+    public function getDataFormat ($format) {
+        foreach ($this->getDatas () as $data)
+        {
+            if ($data->format == $format)
+            {
+                return $data;
+            }
+        }
+        return NULL;
+    }
+    
     public function getFilePath ($extension, $idData = NULL, $relative = false)
     {
         $file = NULL;
diff --git a/bookdetail.php b/bookdetail.php
index 9dae567..50eb4b0 100644
--- a/bookdetail.php
+++ b/bookdetail.php
@@ -24,10 +24,10 @@ $book->getLinkArray ();
         </div>
         <div class="download">
 <?php
-            foreach ($book->format as $key => $format)
+            foreach ($book->getDatas() as $data)
             {
 ?>    
-                <div class="button buttonEffect"><a href="<?php echo "download/" . $format[0] . "/" . urlencode ($format[1]) ?>"><?php echo $key ?></a></div>
+                <div class="button buttonEffect"><a href="<?php echo $data->getHtmlLink () ?>"><?php echo $data->format ?></a></div>
 <?php
             }
 ?>
diff --git a/data.php b/data.php
index 815e6d5..ed3864a 100644
--- a/data.php
+++ b/data.php
@@ -47,6 +47,10 @@ class Data extends Base {
         return self::getLink ($this->book, $this->extension, $this->getMimeType (), $rel, $this->getFilename (), $this->id, $title);
     }
     
+    public function getHtmlLink () {
+        return "download/" . $this->id . "/" . urlencode ($this->getFilename ());
+    }
+    
     public static function getLink ($book, $type, $mime, $rel, $filename, $idData, $title = NULL)
     {
         global $config;
diff --git a/index.php b/index.php
index 6647763..246a9c1 100644
--- a/index.php
+++ b/index.php
@@ -161,9 +161,9 @@
             <?php
                 foreach ($config['cops_prefered_format'] as $format)
                 {
-                    if (array_key_exists($format, $entry->book->format)) {
+                    if ($data = $entry->book->getDataFormat ($format)) {
             ?>    
-                <div class="button buttonEffect"><a href="<?php echo "download/" . $entry->book->format [$format][0] . "/" . urlencode ($entry->book->format [$format][1]) ?>"><?php echo $format ?></a></div>
+                <div class="button buttonEffect"><a href="<?php echo $data->getHtmlLink () ?>"><?php echo $format ?></a></div>
             <?php
                     }
                 }