diff --git a/base/modules/psb_inter_desc_type.f90 b/base/modules/psb_inter_desc_type.f90
index a01598a1..899c666b 100644
--- a/base/modules/psb_inter_desc_type.f90
+++ b/base/modules/psb_inter_desc_type.f90
@@ -1,3 +1,39 @@
+!!$ 
+!!$              Parallel Sparse BLAS  v2.0
+!!$    (C) Copyright 2006 Salvatore Filippone    University of Rome Tor Vergata
+!!$                       Alfredo Buttari        University of Rome Tor Vergata
+!!$ 
+!!$  Redistribution and use in source and binary forms, with or without
+!!$  modification, are permitted provided that the following conditions
+!!$  are met:
+!!$    1. Redistributions of source code must retain the above copyright
+!!$       notice, this list of conditions and the following disclaimer.
+!!$    2. Redistributions in binary form must reproduce the above copyright
+!!$       notice, this list of conditions, and the following disclaimer in the
+!!$       documentation and/or other materials provided with the distribution.
+!!$    3. The name of the PSBLAS group or the names of its contributors may
+!!$       not be used to endorse or promote products derived from this
+!!$       software without specific written permission.
+!!$ 
+!!$  THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+!!$  ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+!!$  TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+!!$  PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE PSBLAS GROUP OR ITS CONTRIBUTORS
+!!$  BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+!!$  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+!!$  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+!!$  INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+!!$  CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+!!$  ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+!!$  POSSIBILITY OF SUCH DAMAGE.
+!!$ 
+!!$  
+!
+!
+! package: psb_inter_descriptor_type
+!    Defines facilities for mapping between vectors belonging
+!    to different spaces.
+!
 module psb_inter_descriptor_type
   use psb_spmat_type
   use psb_descriptor_type