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          if to any Seller:

               Zapata Corporation
               1717 St. James Place, Suite 550
               Houston, Texas 77056
               Attn:   Joseph L. von Rosenberg, III, Esq.
                       Vice President, General Counsel and Corporate Secretary

          with required copy (which shall not constitute notice) to:

               Mr. Avram A. Glazer
               President and Chief Executive Officer
               18 Stoney Clover Lane
               Pittsford, New York 14534

                    and

               John D. Held, Esq.
               Liddell, Sapp, Zivley, Hill & LaBoon, L.L.P.
               3500 Texas Commerce Tower
               Houston, Texas 77002

          if to the Purchasers:

               Enterra Corporation
               13100 Northwest Freeway, Sixth Floor
               Houston, Texas 77040
               Attn:  President

          with required copy (which shall not constitute notice) to:

               Weatherford International Incorporated
               1360 Post Oak Blvd., Suite 1000
               Houston, Texas 77056
               Attn: H. Suzanne Thomas, Esq.

                    and

               David R. King, Esq.
               Morgan, Lewis & Bockius
               2000 One Logan Square
               Philadelphia, Pennsylvania 19103

or to such other address as the person to whom notice is given may have
previously furnished to the others in writing in the manner set forth above
(provided that notice of any change of address shall be effective only upon
receipt thereof).

     Section 12.10 Governing Law. This Agreement shall be governed by and
construed in accordance with the laws of the State of Texas, regardless of the
laws that might otherwise govern under applicable principles of conflicts of
laws thereof.

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