Exhibit 4 Joint Filing Agreement The undersigned agree that the foregoing Amendment No. 4 to Schedule 13D, dated June 17, 1998, is being filed with the Securities and Exchange Commission on behalf of each of the undersigned pursuant to Rule 13d-1(f)....

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                                    Exhibit 4
                             Joint Filing Agreement




                  The  undersigned  agree that the foregoing  Amendment No. 4 to
Schedule  13D,  dated June 17,  1998,  is being  filed with the  Securities  and
Exchange  Commission  on  behalf  of each of the  undersigned  pursuant  to Rule
13d-1(f).

Dated:  June 17, 1998

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