diff -r 5cd8c3065c38 -r bc18286e55b2 server/src/app/Models/Document.php
--- a/server/src/app/Models/Document.php	Tue Feb 23 17:47:57 2016 +0100
+++ b/server/src/app/Models/Document.php	Tue Feb 23 17:57:46 2016 +0100
@@ -354,17 +354,22 @@
                 $this->getContributors()
             );
 
-            return [
+            $res = [
                 'id' => $this->getId(),
                 'uri' => $this->getUri(),
                 'title' => $this->getTitleValue(),
                 'language' => $this->getLanguageValue(),
-                'language_resolved' => $this->getLanguageResolved(),
                 'modified' => $this->getModifiedValue(),
                 'publishers' => $publishers,
                 'contributors' => $contributors,
                 'mediaArray'=> $mediaArray
             ];
+
+            if($this->language_resolved) {
+                $res['language_resolved'] = $this->getLanguageResolved();
+            }
+
+            return $res;
         }
     }