
<PAGE>

                                             Page 9 of 9 Pages

                            EXHIBIT A-1

          Pursuant to Rule 13d-1(f)(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 agree
that the Schedule 13D Amendment No. 2 to the statement on Schedule 13D to
which this Exhibit is attached is filed on behalf of each of them.



                                /S/ S. PHILLIP HORSLEY
                                    S. PHILLIP HORSLEY



                                   /S/ GARY L. BRIDGE
                                    GARY L. BRIDGE

