Exhibit 3.6(d)

                                    BYLAWS OF

                            ALBERTA INVESTMENTS, INC.

                                   ARTICLE ONE

                                REGISTERED OFFICE

     1.01. The registered office of the corporation is located at 6201
Hillcrest, Dallas, Texas 75205, and the name of the registered agent is
Christopher G. Sharp.

                                   ARTICLE TWO

                             SHAREHOLDERS' MEETINGS

                                PLACE OF MEETINGS

     2.01. All meetings of the shareholders shall be held at the registered
office of the corporation, or any other place within or without this State, as
may be designated for that purpose from time to time by the Board of Directors.

                             TIME OF ANNUAL MEETING

     2.02. The annual meetings of the shareholders shall be held each year at
10:00 a.m. on the first Monday in October. If this day falls on a legal holiday,
the annual meeting shall be held at the same time on the next following business
day thereafter.

                                NOTICE OF MEETING

     2.03. Notice of the meeting, stating the place, day, and hour of the
meeting, and in case of a special meeting, the purpose given in writing to each
shareholder entitled to vote at the meeting at least ten (10) but not more than
fifty (50) days before the date of the meeting either personally or by mail or
other means of written communication, addressed to the shareholder at his
address appearing on the books of the corporation or given by him to the
corporation for the purpose of notice. Notice of adjourned meetings is not
necessary unless the meeting is adjourned for thirty (30) days or more, in which
case notice of the adjourned meeting shall be given as in the case of any
special meeting.

                                SPECIAL MEETINGS

     2.04. Special meetings of the shareholders for any purpose or purposes
whatsoever may be called at any time by the President, or by the Board of
Directors, or by any two (2) or more Directors, or by one or more shareholders,
holding not less than one-tenth (1/10) of all the shares entitled to vote at the
meeting.


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                                     QUORUM

     2.05. A majority of the voting shares constitutes a quorum for the
transaction of business. Business may be continued after withdrawal of enough
shareholders to leave less than a quorum.

                                     VOTING

     2.06. Only persons in whose names shares appear on the share records of the
corporation on the date on which notice of the meeting is mailed shall be
entitled to vote at such meeting, unless some other day is fixed by the Board of
Directors for the determination of shareholders of record. Voting for the
election of Directors shall be by voice unless any shareholder demands a ballot
vote before the voting begins. Shareholders will not be permitted to cumulate
their shares for purposes of voting for Directors.

                                     PROXIES

     2.07. Every person entitled to vote or execute consents may do so either in
person or by written proxy executed in writing by the shareholder or his duly
authorized attorney in fact.

                              CONSENT OF ABSENTEES

     2.08. No defect in the calling of noticing of a shareholders' meeting will
affect the validity of any action at the meeting if a quorum was present, and if
each shareholder not present in person or by proxy signs a written waiver of
notice, consent to the holding of the meeting, or approval of the minutes,
either before or after the meeting, and such waivers, consents, or approvals are
filed with the corporate records or made a part of the minutes of the meeting.

                   ACTION WITHOUT MEETING: TELEPHONE MEETINGS

     2.09. Action may be taken by shareholders without a meeting if each
shareholder entitled to vote signs a written consent to the action and such
consents are filed with the Secretary of the corporation. Shareholders, members
of the Board of Directors, or members of any committee designated by such Board,
may participate in and hold a meeting of such shareholders, board or committee
by means of conference telephone or similar communications equipment by means of
which all persons participating in the meeting can hear each other, and
participation in a meeting pursuant to this provision shall constitute presence
in person at such meeting, except where a person participates in the meeting for
the express purpose of objecting to the transaction of any business on the
ground-that the meeting is not lawfully called or convened.


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                                  ARTICLE THREE

                                    DIRECTORS

                                     POWERS

     3.01. The Directors shall act only as a board and an individual Director
shall have no power as such. All corporate powers of the corporation shall be
exercised by, or under the authority of, and the business and affairs of the
corporation shall be controlled by the Board of Directors, subject, however, to
such limitations as are imposed by law, the articles of incorporation, or these
Bylaws, as to actions to be authorized or approved by the shareholders. The
Board of Directors may, by contract or otherwise, give general or limited or
special power and authority to the officers and employees of the corporation to
transact the general business, or any special business of the corporation, and
may give powers of attorney to agents of the corporation to transact any special
business requiring such authorization.

                      NUMBER AND QUALIFICATION OF DIRECTORS

     3.02. The authorized number of Directors of this corporation shall be two.
The Directors need not be shareholders of this corporation or residents of
Texas. The number of Directors may be increased or decreased from time to time
by amendment to these Bylaws but no decrease shall have the effect of shortening
the term of any incumbent Director. Any directorship to be filled by reason of
an increase in the number of Directors shall be filled by election at an annual
meeting or at a special meeting of shareholders called for that purpose.

                           ELECTION AND TERM OF OFFICE

     3.03. The Directors shall be elected annually by the shareholders entitled
to vote, and shall hold office until their respective successors are elected, or
until their death, resignation, or removal.

                                    VACANCIES

     3.04. Vacancies in the Board of Directors may be filled by a majority of
the remaining Directors, though less than a quorum, or by a sole remaining
Director. The shareholders may elect a Director at any time to fill any
vacancies not filled by the Directors.

                              REMOVAL OF DIRECTORS

     3.05. The entire Board of Directors or any individual Director may be
removed from office with or without cause by vote of the holders of a majority
of the shares entitled to vote for directors, at any regular or special meeting
of shareholders.

                                PLACE OF MEETINGS

     3.06. All meetings of the Board of Directors shall be held at the principal
office of the corporation or at such place within or without the State as may be
designated from time to time by resolution of the Board or by written consent of
all of the members of the Board.


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                       SPECIAL MEETINGS - CALL AND NOTICE

     3.08. Special meetings of the Board of Directors for any purpose shall be
called at any time by the President, or if he is absent or unable or refuses to
act, by any two Directors. Written notices of the special meetings, stating the
time, and in general terms and purpose or purposes thereof, shall be mailed or
telegraphed or personally delivered to each Director not later than the day
before the day appointed for the meeting.

                                     QUORUM

     3.09. A majority of the authorized number of Directors shall be necessary
to constitute a quorum for the transaction of business, except to adjourn as
hereinafter provided. Every act or decision done or made by a majority of the
Directors present shall be regarded as the act of the Board of Directors, unless
a greater number be required by law or by the articles of incorporation.

                          BOARD ACTION WITHOUT MEETING

     3.10. Any action required or permitted to be taken by the Board of
Directors, may be taken without a meeting, and with the same force and effect as
a unanimous vote of Directors, if all members of the Board shall individually or
collectively consent in writing to such action. Directors may also participate
in telephone meetings as provided in 2.09 of these Bylaws.

                              ADJOURNMENT - NOTICE

     3.11. A quorum of the Directors may adjourn any Directors' meeting to meet
again at a stated day and hour. Notice of the time and place of holding an
adjourned meeting need not be given to absent Directors if the time and place is
fixed at the meeting adjourned. In the absence of a quorum, a majority of the
Directors present at any Directors' meeting, either regular or special, may
adjourn from time to time until the time fixed for the next regular meeting of
the Board.

                               CONDUCT OF MEETINGS

     3.12. The Chairman of the Board of Directors, or in his absence, any
Director selected by the Directors present, shall preside at meetings of the
Board of Directors. The Secretary of the corporation, or in his absence, any
person appointed by the presiding officer, shall act as Secretary of the Board
of Directors.

                                  COMPENSATION

     3.13. Directors and members of committees may receive such compensation, if
any, for their services, and such reimbursement for expenses, as may be fixed or
determined by resolution of the Board.


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                    INDEMNIFICATION OF DIRECTORS AND OFFICERS

     3.14. The Board of Directors may authorize the corporation to pay expenses
incurred by, or to satisfy a judgment or fine rendered by levied against present
or former Directors, officers, or employees of this corporation as provided by
Article 2.02(a)(16) of the Business Corporation Act.

                                  ARTICLE FOUR

                                    OFFICERS

                              TITLE AND APPOINTMENT

     4.01. The officers of the corporation shall be a President and a Secretary,
and such assistants and other officers as the Board of Directors shall from time
to time determine. Any two offices, except President and Secretary, may be held
by one person. All officers shall be elected by and hold office at the pleasure
of the Board of Directors, which shall fix compensation and tenure of all
officers.

                          POWERS AND DUTIES OF OFFICERS

     4.02. The officers of the corporation shall have the powers and duties
generally ascribed to the respective officers and such additional authority or
duty as may from time to time be established by the Board of Directors.

                                  ARTICLE FIVE

                            EXECUTION OF INSTRUMENTS

     5.01. The Board of Directors may, in its discretion, determine the method
and designate the signatory officer or officers, or other person or persons, to
execute any corporate instrument or document, or to sign the corporate name
without limitation, except where otherwise provided by law, and such execution
or signature shall be binding upon the corporation.

                                   ARTICLE SIX

                         ISSUANCE AND TRANSFER OF SHARES

                     CERTIFICATES FOR PAID AND UNPAID SHARES

     6.01. The Corporation shall deliver certificates representing all shares to
which shareholders are entitled, which certificates shall be in such form and
devise as the Board of Directors may provide. Each certificate shall bear upon
its face the statement that the corporation is organized in Texas, the name in
which it is issued, the number and class of shares and series, and the par value
or a statement that the shares are without par value. The President and the
Secretary or an Assistant Secretary, which signatures may be in facsimile if the
certificates are to be countersigned by a transfer agent or registered by a
registrar. The certificates shall contain on the faces or backs such recitations
or references as are required by laws.


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                           REPLACEMENT OF CERTIFICATES

     6.02. No new certificates shall be issued until the former certificate or
shares represented thereby shall have been surrendered and cancelled, except in
the case of lost or destroyed certificates for which the Board of Directors may
order new certificates to be issued upon such terms, conditions, and guarantees
as the Board may see fit to impose, including the filing of sufficient
indemnity.

                               TRANSFER OF SHARES

     6.03. Shares of the corporation may be transferred by endorsement by the
signature of the owner, his agent, attorney, or legal representative, and the
delivery of the certificate. The transferee in any transfer of shares shall be
deemed to have full notice of, and to consent to, the bylaws of the corporation
to the same extent as if he had signed a written assent thereto.

                                  ARTICLE SEVEN

                               RECORDS AND REPORTS

                         INSPECTION OF BOOKS AND RECORDS

     7.01. All books and records provided for by statute shall be open to
inspection of the shareholders from time to time and to the extent expressly
provided by statute, and not otherwise. The directors may examine such books and
records at all reasonable times.

                          CLOSING STOCK TRANSFER BOOKS

     7.02. The Board of Directors may close the transfer books in their
discretion for a period not exceeding fifty (50) days preceding any meeting,
annual or special, of the shareholders, or the day appointed for the payment of
a dividend.

                                  ARTICLE EIGHT

                               AMENDMENT OF BYLAWS

     8.01. The power to alter, amend, or repeal these bylaws is vested in the
Directors, subject to repeal or change by action of the shareholders.

                           SIGNATURES AND ATTESTATION

     Adopted by the Board of Directors on the [17 day, September, 1983].


                                        [signed]
                                        ----------------------------------------
                                        Gerald A. Berkhold, Director


                                        [signed]
                                        ----------------------------------------
                                        Duncan Steele Curry, Director


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Attest:


[signed]
- -------------------------------------
Christopher G. Sharp, Secretary


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