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EXHIBIT 99.1
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 agrees that the
statement to which this Exhibit is attached is filed on behalf of each of them
in the capacities set forth below.
/s/ DAVID S. HUNT
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David S. Hunt, individually and as
attorney-in-fact for:
TOSI, L.P. (1)
PITMAN PROPERTY CORP. (2)
J. W. BEAVERS, JR. (3)
(1) A power of attorney authorizing David S. Hunt to act on behalf of TOSI,
L.P. previously has been filed with the Commission.
(2) A power of attorney authorizing David S. Hunt to act on behalf of
Pitman Property Corp. previously has been filed with the Commission.
(3) A power of attorney authorizing David S. Hunt to act on behalf of J. W.
Beavers, Jr. previously has been filed with the Commission.
