diff --git a/doc/salome/gui/SMESH/input/extrusion.doc b/doc/salome/gui/SMESH/input/extrusion.doc
index cb061b314..4813eee5c 100644
--- a/doc/salome/gui/SMESH/input/extrusion.doc
+++ b/doc/salome/gui/SMESH/input/extrusion.doc
@@ -64,7 +64,7 @@ The following dialog common for line and planar elements will appear:
   <li>Specify the number of steps.</li>
   <li>If you activate <b>Generate Groups</b> check-box, the created
     elements contained in groups will be included into new groups named
-    by pattern "<old group name>_extruded". </li>
+    by pattern "<old group name>_extruded" and "<old group name>_top".</li>
 </ul>
 
 <li>Click \b Apply or <b> Apply and Close</b>  button to confirm the operation.</li>