diff --git a/src/Plugin/OaiMetadataMap/DgiStandard.php b/src/Plugin/OaiMetadataMap/DgiStandard.php
index 0221935..04fe8e7 100644
--- a/src/Plugin/OaiMetadataMap/DgiStandard.php
+++ b/src/Plugin/OaiMetadataMap/DgiStandard.php
@@ -255,6 +255,9 @@ protected function addFields(ContentEntityInterface $entity) {
         $this->elements['edm:preview'][] = $file->createFileUrl(FALSE);
       }
     }
+
+    $this->addPersistentUrl($entity, 'dcterms:identifier', TRUE);
+    $this->addThumbnail($entity, 'dcterms:identifier');
   }
 
   /**