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                                                             Page  8 of 9  Pages
                                  EXHIBIT 2                  -------------------

                 MORGAN STANLEY, DEAN WITTER, DISCOVER & CO.

                           SECRETARY'S CERTIFICATE




        I, Charlene R. Herzer, a duly elected and acting Assistant Secretary of
Morgan Stanley, Dean Witter, Discover & Co., a corporation organized and
existing under the laws of the State of Delaware (the "Corporation"), certify
that as approved by a Unanimous Consent of Directors in Lieu of a Meeting dated
as of May 31, 1997, the following persons are each authorized to sign reports
to be filed under Sections 13 and 16 of the Securities Exchange Act of 1934 on
behalf of the Corporation, and such authorizations are in full force and
effect as of this date:

                             Stuart J.M. Breslow
                             Robert G. Koppenol
                             Bruce Bromberg
                             Robin Sherak

        IN WITNESS WHEREOF, I have hereunto set my name and affixed the seal of
the Corporation as of the 3rd day of June, 1997.


                                          /s/ Charlene R. Herzer
                                         ------------------------
                                             Charlene R. Herzer
                                             Assistant Secretaty

