diff --git a/objets.py b/objets.py
index 18e0588..c4f4ad9 100644
--- a/objets.py
+++ b/objets.py
@@ -534,6 +534,7 @@ class proprio(CransLdapObject):
     def __init__(self, conn, dn, mode='ro', ldif=None):
         super(proprio, self).__init__(conn, dn, mode, ldif)
         self._machines = None
+        self._factures = None
         
     def sursis_carte(self):
         for h in self['historique'][::-1]:
@@ -608,6 +609,14 @@ class proprio(CransLdapObject):
                 m._proprio = self
         return self._machines
 
+    def factures(self):
+        """Renvoie la liste des factures"""
+        if self._factures is None:
+            self._factures = self.conn.search(u'fid=*', dn = self.dn, scope = 1, mode=self.mode)
+            for m in self._factures:
+                m._proprio = self
+        return self._factures
+
     def delete(self, comm="", login=None):
         """Supprimme l'objet de la base LDAP. En supprimant ses enfants d'abord."""
         if login is None: