diff --git a/htdocs/fourn/facture/pre.inc.php3 b/htdocs/fourn/facture/pre.inc.php3
index 8c819571b30..92582f44a70 100644
--- a/htdocs/fourn/facture/pre.inc.php3
+++ b/htdocs/fourn/facture/pre.inc.php3
@@ -20,6 +20,7 @@
  *
  */
 require("../../main.inc.php3");
+require("../../facturefourn.class.php");
 
 function llxHeader($head = "", $urlp = "") {
   global $user, $conf;