Changed index.php logic

site/public/index.php

   <?php
     $publication_details = get_publication_details($random_record['doc_ref']);
 
-    if ($publication_details['original_title']):
+    if (isset($publication_details['original_title'])):
   ?>
 
     Original language title:
   ?>
 
   <?php
-    if ($publication_details['original_abstract']):
+    if (isset($publication_details['original_abstract'])):
   ?>
 
     Original language abstract: