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Enterra Corporation 
September 20, 1995
Page 2

of resolutions to be submitted to the stockholders of Zapata

 relating to the 
Sale Agreement.

  Because Enterra and Enterra Sub are relying on the foregoing agreement by the 
Trust in entering into the Sale Agreement, the Trust hereby confirms that its 
agreement set forth in the preceding paragraph constitutes a binding and 
irrevocable agreement on its part.

                                                Very truly yours,

                                                MALCOLM I. GLAZER TRUST



                                                By /s/ Malcolm I. Glazer, 
                                                       Trustee