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                                  SIGNATURES

  The Plan. Pursuant to the requirements of the Securities Exchange Act of 1934,
the trustees (or other persons who administer the employee benefit plan) have 
duly caused this annual report to be signed on behalf of the undersigned
hereto duly authorized.


                                                  ZAPATA HAYNIE CORPORATION
                                                  Profit Sharing/Savings Plan

                                                  /s/ Thomas H. Bowersox
March 29, 1994                                    --------------------------
                                                  Thomas H. Bowersox
                                                  Vice President