diff --git a/main/exercice/exercice_history.php b/main/exercice/exercice_history.php
index 833d98878e..f69e133d5d 100755
--- a/main/exercice/exercice_history.php
+++ b/main/exercice/exercice_history.php
@@ -24,9 +24,9 @@ $show=(isset($_GET['show']) && $_GET['show'] == 'result')?'result':'test'; // mo
 	Libraries
 */
 
-require_once(api_get_path(LIBRARY_PATH).'document.lib.php');
+require_once api_get_path(LIBRARY_PATH).'document.lib.php';
 //include(api_get_path(LIBRARY_PATH).'mail.lib.inc.php');
-include(api_get_path(LIBRARY_PATH).'usermanager.lib.php');
+require_once api_get_path(LIBRARY_PATH).'usermanager.lib.php';
 
 /*
 	Constants and variables