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Exhibit 3.15

                            ARTICLES OF INCORPORATION
                                       OF
                                 VALLEY HI, INC.

         The undersigned, a natural person of the age of eighteen years or more,
acting as incorporator of this corporation under the Colorado Corporation Act,
adopts the following Articles of Incorporation for this corporation:

                                    ARTICLE I
                               NAME OF CORPORATION

                 The name of the corporation is Valley Hi, Inc.

                                   ARTICLE II
                             DURATION OF CORPORATION

                    The period of its duration is perpetual.

                                   ARTICLE III
                               PURPOSES AND POWERS

         The purposes and powers of the corporation shall be as follows:

         The purpose of the corporation shall be to transact all lawful business
for which corporations may be incorporated pursuant to the Colorado Corporation
Code, as amended. The corporation shall have the power to do all and everything
necessary, suitable and proper for the accomplishment of its purpose.

                                   ARTICLE IV
                                     CAPITAL

         The aggregate number of shares the corporation shall have authority to
issue is 100,000 shares of common stock having a par value of $1.00 per share.

                                    ARTICLE V
                                     VOTING

         Cumulative voting shall not be allowed.

                                   ARTICLE VI
                               PRE-EMPTIVE RIGHTS

         The shareholders shall have no pre-emptive rights to acquire additional
or treasury shares of the corporation or securities convertible into shares or
carrying stock purchase warrants or privileges.

                                   ARTICLE VII
                        ADOPTION AND AMENDMENT OF BY-LAWS

         The By-Laws of the corporation shall be adopted by its Board of
Directors. The power to alter or amend or repeal the By-Laws or adopt new
By-Laws shall be vested in the Board of Directors, but the shareholders may also
alter, amend or repeal the By-Laws or adopt new By-Laws. The By-Laws may contain
any provisions for the regulation and management of the affairs of the
corporation not inconsistent with statute or the Articles of Incorporation.

                                  ARTICLE VIII
                           REGISTERED OFFICE AND AGENT

         The address of the initial registered office of the corporation is 2010
46th Avenue, Suite B-1, Greeley, Colorado 80634.

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         The name of its registered agent at such address is David Kremser.

                                   ARTICLE IX
                       DEALINGS OF OFFICERS AND DIRECTORS

         In the absence of fraud, no contract or other transaction between this
corporation and any other corporation or any partnership or association shall be
affected or invalidated by the fact that any director or officer of the
corporation is pecuniarily or otherwise interested in or is a director, member
or officer of such other corporation or of such firm, association or partnership
or is a party to or is pecuniarily or otherwise interested in such contract or
other transaction or in any way connected with any person or persons, firms,
associations, partnership or corporation pecuniarily or otherwise interested
therein, provided that the existence and nature of any such interest, possession
or connection of such director or officer shall be disclosed or shall have been
known to the directors present at any meeting of the Board of Directors at which
action on any such contract or transaction shall have been taken and provided
further that the fact of such relationship is disclosed or known to the
shareholders entitled to vote and they authorize, approve, or ratify the
contract or transaction by vote or written consent and the contract or
transaction is fair and reasonable to the corporation.

         A director of this corporation shall not be personally liable to the
corporation or to its shareholders for monetary damages for breach of fiduciary
duty as a director, except for liability to this corporation or to its
shareholders for monetary damages for (i) any breach of the director's duty of
loyalty to the corporation or to its shareholders; (ii) acts or omissions not in
good faith or which involve intentional misconduct or a knowing violation of
law; (iii) acts specified in Section 7-5-114 of the Colorado Corporation Code;
or (iv) any transaction from which the director derived an improper personal
benefit.

         If the Colorado Corporation Code is hereafter amended to authorize the
further elimination or limitation of the liability of a director, then the
liability of a director of the corporation shall be eliminated or limited to the
fullest extent permitted by the Colorado Corporation Code, as so amended.

         Any repeal or modification of the foregoing provisions of this Article
Ninth by the shareholders or the corporation shall not affect adversely any
right or protection of a director of the corporation in respect of any acts or
omissions of such director occurring prior to the time of such repeal or
modification.

         Any director may be counted in determining the existence of a quorum
and may vote at any meeting of the Board of Directors of the corporation for the
purpose of authorizing any such contract or transaction with like force and
effect as if he were not so interested, or were not a director, member or
officer of such other corporation, firm, association or partnership.

                                    ARTICLE X
                          INDEMNIFICATION OF DIRECTORS
                         OFFICERS, EMPLOYEES AND AGENTS

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         Pursuant to Section 7-3-101 of the Colorado Revised Statutes, as
amended, each director, officer, employee or agent of the corporation (and his
heirs, executors and administrators) shall be indemnified by the corporation
against expenses reasonably incurred by or imposed upon him in connection with
or arising out of any action, suit or proceeding in which he may be involved or
to which he may be made a party by reason of his being or having been a
director, officer, employee or agent of the corporation, or at its request, of
any other corporation of which it is a shareholder or creditor and from which he
is not entitled to be indemnified (whether or not he continues to be a director
or officer at the time of imposing or incurring such expenses), except in
respect of matters as to which he shall be finally adjudged in such action, suit
or proceeding to be liable for negligence or misconduct; or in the event of a
settlement of any such action, suit or proceeding, indemnification shall be
provided only in connection with such matters covered by the settlement as to
which the corporation is advised by counsel that the person to be indemnified
did not commit a breach of duty. The foregoing right of indemnification shall
not be exclusive of other rights to which he may be entitled under applicable
state statute.

                                   ARTICLE XI
                                INITIAL DIRECTORS

         The number of directors of the corporation shall not be less than three
unless there are fewer than three shareholders of the corporation in which event
the number of directors may equal the number of shareholders. The initial
director of the corporation shall be David Kremser, 2010 46th Avenue, Suite B-1,
Greeley, Colorado 80634.

                                   ARTICLE XII
                                  INCORPORATOR

         The name and address of the incorporator is:

         NAME                               ADDRESS
         ----                               -------

         David Kremser                      2010 46th Avenue, Suite B-1
                                            Greeley, Colorado 80634

         DATED at Greeley, Colorado this 31st day of August, 1989.

                                                           /s/   David Kremser
                                                           --------------------

STATE OF COLORADO)
                 )ss
COUNTY OF WELD   )

         I, Stephanie L. Orlofsky, Notary Public hereby certify that on the
31st Day of August, 1989, personally appeared before me David Kremser, who
being by me first duly sworn, declared that he is the person who signed the
foregoing document as incorporator, and that the statements therein contained
are true.

         IN WITNESS WHEREOF, I have hereunto set my hand and seal this 31st day
of August, 1989.

         My commission expires: 10/12/92.

                                                           Stephanie L. Orlofsky
                                                           ---------------------


                                                                   Notary Public

[SEAL]


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               ARTICLES OF AMENDMENT TO ARTICLES OF INCORPORATION

         Pursuant to the provisions of the Colorado Corporation Code, the
undersigned corporation adopts the following Articles of Amendment to its
Articles of Incorporation:

         FIRST:  The name of the corporation is Valley Hi, Inc.

         SECOND: The following amendment to the Articles of Incorporation was
adopted on October 19, 1990 by unanimous vote of the shareholder:

         ARTICLE I of the Articles of Incorporation are hereby amended as
follows:

                               NAME OF CORPORATION

         The name of the corporation is Amberwood Court, Inc.

                                                         VALLEY HI, INC.
                                                            /s/

                                                         President
                                                            /s/

                                                         Secretary