diff --git a/product/ERP5/interfaces/downloadable.py b/product/ERP5/interfaces/downloadable.py
index 80337b2b759c5b5df21e8d0c8423f3aeae3dfa56..2de4acaf9665d6169dd6897737db125248db2e20 100644
--- a/product/ERP5/interfaces/downloadable.py
+++ b/product/ERP5/interfaces/downloadable.py
@@ -33,7 +33,7 @@ class IDownloadable(Interface):
   """
   Downloadable interface specification
 
-  Documents which implement the IDownloadable can be downloaded
+  Documents which implement IDownloadable can be downloaded
   directly from their URL using any format specified as a parameter.
   """
 
@@ -51,4 +51,10 @@ class IDownloadable(Interface):
 
     kw -- optional conversion parameters
     """
- 
\ No newline at end of file
+
+  def getStandardFileName():
+    """
+    Returns a standard file name for the document to download.
+    This method is the reverse of
+    IMetadataDiscoverable.getPropertyDictFromFileName.
+    """ 
\ No newline at end of file