Joint Filing Agreement

                                                                       EXHIBIT 7
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                             Joint Filing Agreement

                  Pursuant to Rule 13d-1(k)(1) promulgated under the Securities
Exchange Act of 1934, as amended, the undersigned agree that the Statement on
Schedule 13D to which this exhibit is attached is filed on behalf of each of
them in the capacities set forth below.

Dated:  August 18, 2003


                                   EXOR GROUP S.A.


                                   By:                  *
                                        ---------------------------------------
                                        Xxxxx X. Xxxxxxxxxx
                                        Attorney-in-Fact



                                   Istituto Finanziario Industriale S.p.A.


                                   By:                  *
                                        ---------------------------------------
                                        Xxxxx X. Xxxxxxxxxx
                                        Attorney-in-Fact



                                   Xxxxxxxx Xxxxxxx e C. X.x.x.xx.


                                   By:                  *
                                        ---------------------------------------
                                        Xxxxx X. Xxxxxxxxxx
                                        Attorney-in-Fact



                                   /s/ Xxxxx X. Xxxxxxxxxx
                                   --------------------------------------------
                                   * Xxxxx X. Xxxxxxxxxx
                                   Attorney-in-Fact