diff --git a/htdocs/core/class/cunits.class.php b/htdocs/core/class/cunits.class.php
index 7259592ed41..477b6796a3c 100644
--- a/htdocs/core/class/cunits.class.php
+++ b/htdocs/core/class/cunits.class.php
@@ -427,9 +427,9 @@ class CUnits // extends CommonObject
 	{
 
 		if ($mode == 'short_label') {
-			return dol_getIdFromCode($this->db, $code, 'c_units', 'short_label', 'rowid', 0, ' AND unit_type = "'.$this->db->escape($unit_type).'"');
+			return dol_getIdFromCode($this->db, $code, 'c_units', 'short_label', 'rowid', 0, " AND unit_type = '".$this->db->escape($unit_type)."'");
 		} elseif ($mode == 'code') {
-			return dol_getIdFromCode($this->db, $code, 'c_units', 'code', 'rowid',0, ' AND unit_type = "'. $this->db->escape($unit_type) .'"');
+			return dol_getIdFromCode($this->db, $code, 'c_units', 'code', 'rowid',0, " AND unit_type = '". $this->db->escape($unit_type) ."'");
 		}
 
 		return $code;