diff --git a/Resources/Public/jsDomainModeling/extended/ListField.js b/Resources/Public/jsDomainModeling/extended/ListField.js
index 7ad52b7e..b57e1659 100755
--- a/Resources/Public/jsDomainModeling/extended/ListField.js
+++ b/Resources/Public/jsDomainModeling/extended/ListField.js
@@ -4,10 +4,6 @@
  *    (see line
  **************************************************/
 (function () {
-  var inputEx = YAHOO.inputEx,
-    lang = YAHOO.lang,
-    Event = YAHOO.util.Event,
-    Dom = YAHOO.util.Dom;
 
   /**
    * @class Meta field to create a list of other fields
@@ -26,6 +22,11 @@
 
   YAHOO.util.Event.onDOMReady(function () {
     if (YAHOO.inputEx) {
+      let inputEx = YAHOO.inputEx;
+      let lang = YAHOO.lang;
+      let Event = YAHOO.util.Event;
+      let Dom = YAHOO.util.Dom;
+
       inputEx.ListField = function (options) {
         /**
          * List of all the subField instances