diff --git a/htdocs/resource/class/dolresource.class.php b/htdocs/resource/class/dolresource.class.php
index ad3355e3972..ec184cd856d 100644
--- a/htdocs/resource/class/dolresource.class.php
+++ b/htdocs/resource/class/dolresource.class.php
@@ -56,7 +56,9 @@ class Dolresource extends CommonObject
 	public $type_label;
 	public $tms='';
 
-	var $oldcopy;
+	public $cache_code_type_resource=array();
+
+	public $oldcopy;
 
     /**
      *  Constructor