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                                                                    EXHIBIT 99.A

[ONEOK LOGO] FINANCIAL NEWS
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ONEOK, INC.                         CONTACT:  WELDON WATSON, ONEOK, 918/588-7158
P.O. BOX 871                                MARY BETH JARVIS, KOCH, 316/828-3756
TULSA, OK 74102-0871                   FOR IMMEDIATE RELEASE:  FEBRUARY 25, 1999


                 ONEOK ACQUIRES GATHERING AND PROCESSING ASSETS

         TULSA, Oklahoma -- ONEOK, Inc., and Koch Midstream Enterprises jointly
announced today a letter of intent for ONEOK to acquire all the Oklahoma
midstream natural gas gathering and processing assets of Koch Midstream
Enterprises for $285 million in cash. The assets include eight natural gas
processing plants and approximately 3,250 miles of gathering pipeline connected
to 1,460 gas wells located in Oklahoma. Total capacity of the plants is 515
million cubic feet per day. The transaction is subject to certain conditions,
including approval by regulatory agencies and the boards of directors of both
companies.

         David Kyle, president and chief operating officer of ONEOK, said,
"These assets are located in an area where ONEOK owns significant natural gas
production and development acreage. This will enable the company to continue our
strategic objective of maximizing values in all of our nonregulated natural gas
operations."

         Kyle added, "We have had partial ownership of some of these assets
before but recent natural gas reserve acquisitions and, more importantly, the
opportunity to own gathering systems upstream of the plants will provide greater
opportunity in a highly competitive marketplace. We will be focusing on
improving the utilization of these assets to maximize their future value."

         Koch Midstream Enterprises is a wholly owned subsidiary of Koch
Industries, Inc., a privately held company involved worldwide in virtually all
phases of the oil and gas industry, as well as agriculture, chemicals, energy
services, asphalt products, metals and minerals services, real estate and
financial investments.

         ONEOK, Inc., (NYSE:OKE) is engaged in natural gas intrastate
distribution, transmission, gas processing, gas marketing and oil and gas
production.

                                      # # #

STATEMENTS CONTAINED IN THIS RELEASE THAT INCLUDE COMPANY EXPECTATIONS OR
PREDICTIONS OF THE FUTURE ARE FORWARD-LOOKING STATEMENTS INTENDED TO BE COVERED
BY THE SAFE HARBOR PROVISIONS OF THE SECURITIES ACT OF 1933 AND THE SECURITIES
EXCHANGE ACT OF 1934. IT IS IMPORTANT TO NOTE THAT THE ACTUAL RESULTS OF COMPANY
EARNINGS COULD DIFFER MATERIALLY FROM THOSE PROJECTED IN SUCH FORWARD-LOOKING
STATEMENTS. INFORMATION IS AVAILABLE ON THE INTERNET WORLD WIDE WEB AT
HTTP://WWW.ONEOK.COM.

