Exhibit 99.1

         Pursuant to Rule 13d-1(k)(1)(iii) of Regulation 13D-G of the General
Rules and Regulations of the Securities and Exchange Commission under the
Securities Exchange Act of 1934, as amended, the undersigned agrees that the
statement to which this Exhibit is attached is filed on behalf of each of them
in the capacities set forth below.

                                   ALPINE CAPITAL, L.P.


                                   By:  /s/ Robert W. Bruce III
                                        ---------------------------------------
                                        Robert W. Bruce III,
                                        Manager


                                   /s/ Robert W. Bruce III
                                   --------------------------------------------
                                   ROBERT W. BRUCE III


                                   ALGENPAR, INC.


                                   By:  /s/ J. Taylor Crandall
                                        ---------------------------------------
                                        J. Taylor Crandall,
                                        President


                                   /s/ J. Taylor Crandall
                                   --------------------------------------------
                                   J. TAYLOR CRANDALL


                                   /s/ Susan C. Bruce
                                   --------------------------------------------
                                   SUSAN C. BRUCE


                                   KEYSTONE, INC.


                                   By:  /s/ W.R. Cotham
                                        ---------------------------------------
                                        W.R. Cotham,
                                        Vice President




                                   /s/ W.R. Cotham
                                   --------------------------------------------
                                   W.R. Cotham

                                   Attorney-in-Fact for:

                                   ROBERT M. BASS (1)
                                   THE ANNE T. AND ROBERT M. BASS
                                   FOUNDATION (2)
                                   ANNE T. BASS (3)


                                   THE ROBERT BRUCE MANAGEMENT COMPANY, INC.
                                   DEFINED BENEFIT PENSION TRUST


                                   By:  /s/ Robert W. Bruce III
                                        ---------------------------------------
                                        Robert W. Bruce III,
                                        Trustee
                                            ALPINE CAPITAL, L.P.



(1)  A Power of Attorney authorizing W.R. Cotham, et al., to act on behalf of
Robert M. Bass previously has been filed with the Securities and Exchange
Commission.

(2)  A Power of Attorney authorizing W.R. Cotham, et al., to act on behalf of
The Anne T. and Robert M. Bass Foundation previously has been filed with the
Securities and Exchange Commission.

(3)  A Power of Attorney authorizing W.R. Cotham, et al., to act on behalf of
Anne T. Bass previously has been filed with the Securities and Exchange
Commission.