diff --git a/Classes/Plugin/PageGrid.php b/Classes/Plugin/PageGrid.php
index eb0b76ead..49f6fb095 100644
--- a/Classes/Plugin/PageGrid.php
+++ b/Classes/Plugin/PageGrid.php
@@ -11,6 +11,8 @@
  * LICENSE.txt file that was distributed with this source code.
  */
 
+use Kitodo\Dlf\Common\Helper;
+
 /**
  * Plugin 'Page Grid' for the 'dlf' extension
  *
diff --git a/Classes/Plugin/PageView.php b/Classes/Plugin/PageView.php
index a418df3cf..03093043f 100644
--- a/Classes/Plugin/PageView.php
+++ b/Classes/Plugin/PageView.php
@@ -11,6 +11,8 @@
  * LICENSE.txt file that was distributed with this source code.
  */
 
+use Kitodo\Dlf\Common\Helper;
+
 /**
  * Plugin 'Page View' for the 'dlf' extension
  *