diff --git a/htdocs/product/stock/stats/expedition.php b/htdocs/product/stock/stats/expedition.php
index cc2a10c0592..b3c30f5ce68 100644
--- a/htdocs/product/stock/stats/expedition.php
+++ b/htdocs/product/stock/stats/expedition.php
@@ -267,10 +267,10 @@ if ($id > 0 || !empty($ref)) {
 					$option .= '&limit='.((int) $limit);
 				}
 				if (!empty($search_month)) {
-					$option .= '&search_month='.urlencode($search_month);
+					$option .= '&search_month='.urlencode((string) ($search_month));
 				}
 				if (!empty($search_year)) {
-					$option .= '&search_year='.urlencode($search_year);
+					$option .= '&search_year='.urlencode((string) ($search_year));
 				}
 
 				print '<form method="post" action="'.$_SERVER ['PHP_SELF'].'?id='.$object->id.'" name="search_form">'."\n";
@@ -286,7 +286,7 @@ if ($id > 0 || !empty($ref)) {
 				print_barre_liste($langs->trans("Shipments"), $page, $_SERVER["PHP_SELF"], $option, $sortfield, $sortorder, '', $num, $totalofrecords, '', 0, '', '', $limit, 0, 0, 1);
 
 				if (!empty($page)) {
-					$option .= '&page='.urlencode($page);
+					$option .= '&page='.urlencode((string) ($page));
 				}
 
 				print '<div class="liste_titre liste_titre_bydiv centpercent">';