TERM NOTE

Exhibit 99.4

TERM NOTE


$5,000,000.00 September 24, 2008

FOR VALUE RECEIVED, the undersigned, Boone Pickens Interests, Ltd.
("MAKER"), hereby promises to pay to the order of T. Boone Pickens, Jr.
("PAYEE") the principal sum of FIVE MILLION AND NO/L00 DOLLARS ($5,000,000.00),
together with any interest on the unpaid balance from the date of this note
until maturity at the rate provided below.

The unpaid principal amount of this note and any unpaid accrued
interest thereon shall be due and payable on the earlier of (i) August 30, 2018
or (ii) the date of the acceleration of the maturity of this note in accordance
with the terms of this note.

Maker promises to pay interest on the unpaid principal balance of this
note from the date of this note until the principal balance thereof is paid in
full. Interest shall accrue on the outstanding principal balance of this note
from and including the date of this note to but not including the date of the
maturity of this note at the rate set forth below and shall be due and payable
as it accrues on August 30 of each year of this note, commencing with the first
payment of accrued interest on August 30, 2009, and continuing through and
including maturity. Maker shall pay the accrued interest annually on August 30
of each year of this note, provided that if Maker fails to pay interest in any
year, Maker shall not he considered to be in default on this note. All payments
and prepayments made in accordance with this note shall be applied first to
payment of accrued and unpaid interest and then to payment of unpaid principal.

Interest on the principal balance of this note shall accrue at a rate,
compounded annually, equal to the lesser of (i) 2.38% or (ii) the maximum
nonusurious interest rate as in effect from time to time which may be charged,
contracted for, received or collected by Payee in connection with the
transactions contemplated by and evidenced in this note and all documents
executed in connection with this note ("THE HIGHEST LAWFUL RATE").

Maker may from time to time prepay all or any portion of the
outstanding balance of this note on any Business Day without penalty or premium.
As used herein, a "BUSINESS DAY" shall mean any day other than a Saturday,
Sunday or other day on which banks in Texas are permitted or required by law to
be closed. All payments and prepayments made in accordance with this note in
respect of principal and interest on this note are to be made in lawful money of
the United States of America no later than 12 o'clock noon, central time, in
same day funds, at 8117 Preston, Suite 260, Dallas, Texas 75225, or such other
place as the holder of this note shall designate in writing to Maker. Maker
shall have no right to reborrow under this note any amounts paid or prepaid in
respect of principal or interest on this note.

If any payment or prepayment of principal or interest on this note
shall become due on a day which is not a Business Day, such payment shall be
made on the next succeeding Business Day and such extension of time shall in
such case be included in computing interest in connection with such payment.



In addition to all principal and accrued interest on this note, Maker
agrees to pay (a) all reasonable costs and expenses incurred by all owners and
holders of this note in collecting this note through any probate,
reorganization, bankruptcy or any other proceeding and (b) reasonable attorneys'
fees when and if this note is placed in the hands of an attorney for collection.

All agreements between Maker and Payee, whether now existing or arising
after the date of this note and whether written or oral, are expressly limited
so that in no contingency or event whatsoever shall the amount paid, or agreed
to be paid, to Payee for the use, forbearance, or detention of the money
evidenced by this note or otherwise or for the payment or performance of any
covenant or obligation contained in this note or any other document, agreement
or instrument executed in connection with or given as security for this note,
exceed the Highest Lawful Rate. lf, as a result of any circumstances whatsoever,
fulfillment of any provision of this note or of any of such documents, at the
time performance of such provision shall be due, shall involve transcending the
limit of validity prescribed by applicable usury law, then, ipso facto, the
obligation to be fulfilled shall be reduced to the limit of such validity, and
if, from any such circumstance, Payee shall ever receive interest or anything
which might be deemed interest under applicable law which would exceed the
Highest Lawful Rate, such amount which would be excessive interest shall be
applied to the reduction of the principal amount owing on account of this note
or the amounts owing on other obligations of Maker to Payee and not to the
payment of interest, or if such excessive interest exceeds the unpaid principal
balance of this note and the amounts owing on other obligations of Maker to
Payee, as the case may he, such excess shall be refunded to Maker. In
determining whether or not the interest paid or payable under any specific
contingencies exceeds the Highest Lawful Rate, Maker and Payee shall, to the
maximum extent permitted under applicable law, (a) characterize any nonprincipal
payment as an expense, fee or premium rather than as interest; (b) exclude
voluntary prepayments and the effects thereof; and (c) amortize, prorate,
allocate and spread in equal parts during the period of the full stated term of
this note, all interest at any time contracted for, charged, received or
reserved in connection with the indebtedness evidenced by this note.

If an Event of Default (as defined below in this paragraph) exists,
Payee may (i) declare by written notice to Maker the entire unpaid balance of
this note immediately due and payable, together with accrued interest, and (ii)
exercise any and all other legal or equitable rights afforded under applicable
law. An "Event of Default" shall mean the occurrence of one or more of the
following events: (i) the failure of Maker to pay any amount when it becomes due
and payable under this note, provided that the failure of Maker to pay interest
accrued on this note prior to maturity shall not constitute an Event of Default;
(ii) the failure of Maker to perform and comply with any covenant, agreement, or
condition contained in this note; and (iii) in each case, such failure continues
for 120 days after the Payee gives written notice of such failure to Maker.
Except as otherwise provided in this note, Maker waives presentment of demand
for payment, protest, notice of intent to accelerate, notice of acceleration and
notice of protest and nonpayment.

Maker and any and all endorsers, guarantors and sureties severally
waive grace, presentment for payment, notice of dishonor, notice of intent to
accelerate, notice of acceleration, protest and notice of protest and diligence
in collecting and bringing of suit against any party to this note, and agree to
all modifications, renewals, extensions, substitutions or replacements of this
note or partial payments on this note and to any release or substitution of
security, if any, of this note, in whole or in part, with or without notice,
before or after maturity. This note may be transferred by Payee, and the rights
and privileges of Payee under this note shall inure to the benefit of Payee's
representatives, successors and assigns.



THIS NOTE SHALL BE DEEMED TO BE A CONTRACT UNDER TEXAS LAW AND FOR ALL
PURPOSES SHALL BE CONSTRUED AND ENFORCED IN ACCORDANCE WITH TEXAS LAW AND
APPLICABLE FEDERAL LAWS. Maker further agrees that the consideration furnished
to Maker is related solely to business, commercial, investment or other similar
purposes and not personal, family or agricultural purposes.

THIS WRITTEN AGREEMENT REPRESENTS THE FINAL AGREEMENT BETWEEN THE
PARTIES AND MAY NOT BE CONTRADICTED BY EVIDENCE OF PRIOR, CONTEMPORANEOUS, OR
SUBSEQUENT ORAL AGREEMENTS OF THE PARTIES. THERE ARE NO UNWRITTEN ORAL
AGREEMENTS BETWEEN THE PARTIES.

BOONE PICKENS INTERESTS, LTD.


By: /s/ Robert L. Stillwell
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Robert L. Stillwell, Managing Partner

By: /s/ Ronald D. Bassett
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Ronald D. Bassett, Managing Partner