Document:

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                                                                    Exhibit 4.13

  NUMBER             COMMON SHARES
ZQ
               INCORPORATED UNDER THE LAWS                          SHARES
                OF THE STATE OF ILLINOIS

           THIS CERTIFICATE IS TRANSFERABLE IN
                CHICAGO OR NEW YORK CITY

                    SEE REVERSE FOR                            CUSIP 711030 10 6
                  CERTAIN DEFINITIONS

                           PEOPLES ENERGY CORPORATION

                  THIS
                CERTIFIES
                  THAT

                                      VOID

                 IS THE
                 OWNER
                   OF

        FULLY PAID AND NONASSESSABLE COMMON SHARES WITHOUT PAR VALUE OF

        PEOPLES ENERGY CORPORATION [ILLEGIBLE]

        DATED

[PEOPLES ENERGY CORPORATION ILLINOIS SEAL]

        COUNTERSIGNED AND REGISTERED:                      /s/  Richard E. Terry
            HARRIS TRUST AND SAVINGS BANK
                     (CHICAGO)
                        TRANSFER AGENT AND REGISTRAR.      CHAIRMAN OF THE BOARD

                                                           /s/  [ILLEGIBLE]

                              AUTHORIZED SIGNATURE.                    TREASURER

039518

<Page>

THIS CERTIFICATE ALSO EVIDENCES AND ENTITLES THE HOLDER HEREOF TO CERTAIN RIGHTS
AS SET FORTH IN A RIGHTS AGREEMENT BETWEEN PEOPLES ENERGY CORPORATION AND HARRIS
TRUST AND SAVINGS BANK DATED AS OF MAY 1, 1996 (THE "RIGHTS AGREEMENT"), THE
TERMS OF WHICH ARE HEREBY INCORPORATED HEREIN BY REFERENCE AND A COPY OF WHICH
IS ON FILE AT THE PRINCIPAL EXECUTIVE OFFICES OF PEOPLES ENERGY CORPORATION.
UNDER CERTAIN CIRCUMSTANCES, AS SET FORTH IN THE RIGHTS AGREEMENT, SUCH RIGHTS
WILL BE EVIDENCED BY SEPARATE CERTIFICATES AND WILL NO LONGER BE EVIDENCED BY
THIS CERTIFICATE. PEOPLES ENERGY CORPORATION WILL MAIL TO THE HOLDER OF THIS
CERTIFICATE A COPY OF THE RIGHTS AGREEMENT AS IN EFFECT ON THE DATE OF MAILING
WITHOUT CHARGE WITHIN FIVE BUSINESS DAYS AFTER RECEIPT OF A WRITTEN REQUEST
THEREFOR. UNDER CERTAIN CIRCUMSTANCES SET FORTH IN THE RIGHTS AGREEMENT, RIGHTS
BENEFICIALLY OWNED BY AN ACQUIRING PERSON MAY BECOME NULL AND VOID.

    The following abbreviations, when used in the inscription on the face of
this certificate, shall be construed as though they were written out in full
according to applicable laws or regulations:

    TEN COM --as tenants in common          UNIF GIFT MIN ACT--  CUSTODIAN
                                                             -------------------
    TEN ENT --as tenants by the entireties                   (Cust)      (Minor)
                                                             under Uniform Gifts
                                                             to Minors

    JT TEN  --as joint tenants with right of                 Act
              survivorship and not as tenants                   ----------------
              in common                                              (State)

    Additional abbreviations may also be used though not in the above list.

    FOR VALUE RECEIVED,                  HEREBY SELL, ASSIGN AND TRANSFER UNTO

 PLEASE INSERT SOCIAL SECURITY OR OTHER
     IDENTIFYING NUMBER OF ASSIGNEE

        --------------------

    ----------------------------------------

                                                                          SHARES
REPRESENTED BY THE WITHIN CERTIFICATE AND DO HEREBY IRREVOCABLY CONSTITUTE AND
APPOINT
______________________________________________________________________ ATTORNEY,
TO TRANSFER THE SAID SHARES ON THE BOOKS OF THE WITHIN NAMED COMPANY WITH FULL
POWER OF SUBSTITUTION IN THE PREMISES.

DATED _______________________

AFFIX MEDALLION SIGNATURE
GUARANTEE IMPRINT BELOW                X

                                       X

                                                        SIGNATURE

                                         ---------------------------------------
                                         ABOVE SIGNATURE(S) TO THIS ASSIGNMENT
                                         MUST CORRESPOND WITH THE NAME AS
                                         WRITTEN UPON THE FACE OF THE
                                         CERTIFICATE IN EVERY PARTICULAR,
                                         WITHOUT ALTERATION OR ENLARGEMENT, OR
                                         ANY CHANGE WHATEVER.

                                         THE SIGNATURE(S) MUST BE GUARANTEED BY
                                         AN ELIGIBLE GUARANTOR INSTITUTION SUCH
                                         AS A SECURITIES BROKER/DEALER,
                                         COMMERCIAL BANK & TRUST COMPANY,
                                         SAVINGS AND LOAN ASSOCIATION OR A
                                         CREDIT UNION PARTICIPATING IN A
                                         MEDALLION PROGRAM APPROVED BY THE
                                         SECURITIES TRANSFER ASSOCIATION, INC.<PAGE>

                                                                   Exhibit 10(c)

                              AMENDED AND RESTATED
                             SUPPLEMENTAL RETIREMENT
                                    AGREEMENT

     THIS AMENDED AND RESTATED SUPPLEMENTAL RETIREMENT AGREEMENT (this
"Agreement") is made and entered into as of this 1st day of January 2002 by and
between Banknorth Group, Inc. (formerly known as Peoples Heritage Financial
Group, Inc.), its subsidiaries and affiliates (collectively, the "Corporation"),
and William J. Ryan (the "Executive").

                                  WITNESSETH:

     WHEREAS, the Corporation and the Executive are parties to a certain
Supplemental Retirement Agreement dated as of January 1, 1996, as amended by a
First Amendment to Supplemental Retirement Agreement dated March 27, 2001 (as so
amended, the "Prior Agreement");

     WHEREAS, the Corporation and the Executive wish to amend and restate the
Prior Agreement in its entirety as hereinafter set forth;

     NOW, THEREFORE, in consideration of the foregoing, the mutual covenants and
agreements herein contained, and other good and valuable consideration, the
receipt and sufficiency of which is hereby acknowledged, the Corporation and the
Executive hereby agree, and amend and restate the Prior Agreement in its
entirety, as follows:

                                   ARTICLE ONE

SECTION 1. EMPLOYMENT. This Agreement is not an agreement of employment and
nothing herein shall be deemed to confer on the Executive any right to continued
employment with the Corporation or limit in any way the right of the Corporation
to terminate such employment. The benefits provided under this Agreement are not
part of any salary reduction plan or an arrangement deferring a bonus or a
salary increase.

                                   ARTICLE TWO

SECTION 2.1. NORMAL RETIREMENT BENEFITS. If the Executive continues in
employment with the Corporation until his sixty-fifth (65th) birthday (the
"Normal Retirement Date"), he shall be entitled to a retirement benefit (the
"Normal Retirement Benefit") commencing on the first day of the month next
following his actual retirement (the "Commencement Date") and continuing for
fifteen (15) years certain (the "Payment Period"), payable monthly in the annual
amount of sixty-five percent (65%) of his Benefit Computation Base (defined in
Section 2.2), multiplied by a fraction, not to exceed one (1), the numerator of
which is the actual number of months of the Executive's employment with the
Corporation (including partial months for month of hire and month of
termination) plus sixty-six (66) and the denominator of which is three hundred
(300) months, and reduced by:

     (1) fifty percent (50%) of the Executive's Primary Social Security
     retirement benefit estimated as of the Normal Retirement Date based on the
     Social Security retirement

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     benefit formula assuming level future earnings based on his Benefit
     Computation Base in effect on the date of termination of the Executive's
     employment with the Corporation;

     (2) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, from the
     tax-qualified defined benefit pension plan maintained by the Corporation
     (such plan, as it may hereafter be amended, restated, otherwise modified or
     replaced, is hereinafter referred to as the "Pension Plan");

     (3) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, which is the
     actuarial equivalent (determined as described below) at the date of
     determination of the Normal Retirement Benefit, of that portion of the
     Executive's account balances attributable to contributions by the
     Corporation to any and all qualified defined contribution plans maintained
     by the Corporation; and

     (4) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, attributable to
     contributions by the Corporation (but not any amounts attributable to
     deferrals or contributions by the Executive) from any other qualified or
     non-qualified retirement plan or agreement maintained or entered into by
     the Corporation.

Whenever an "actuarial equivalent" is required to be determined under this
Agreement, such actuarial equivalent shall be determined in the manner provided
for determining actuarial equivalents under the Pension Plan; provided however
that such manner of determination shall be no less favorable to the Executive
than that prescribed for determining actuarial equivalents under the Pension
Plan as in effect on the date of this Agreement.

SECTION 2.2 BENEFIT COMPUTATION BASE. The Executive's Benefit Computation Base
for purposes of Section 2.1 shall be the average of the Executive's compensation
from the Corporation for the five (5) consecutive calendar years during the ten
(10) years preceding the Executive's termination of employment with the
Corporation in which such compensation is the highest (excluding all years of
the Executive's employment by the Corporation after the year in which the Normal
Retirement Date occurs). For the purposes of this Agreement, compensation shall
mean the amount actually paid or made available to the Executive during a
calendar year as remuneration of a kind or nature reported by the Corporation on
the Executive's W-2. Compensation shall also include annual bonuses, any
contributions made on behalf of the Executive by the Corporation pursuant to a
salary reduction agreement under Internal Revenue Code Sections 125, 129 and/or
401(k), and any and all other amounts that would have been reportable by the
Corporation on the Executive's W-2 but for deferral of payment of such amounts
under any agreement or plan or program (other than the Pension Plan), including
any voluntary deferrals and any deferrals required or mandated by the terms of
any agreement or plan or program of the Corporation or action of its Board of
Directors. Compensation shall not include any amounts available to the Executive
pursuant to any Stock Option, Stock Appreciation Right, or Senior Management
Long Term Incentive Plans of the Corporation.

                                       2
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SECTION 2.3 ACCRUED BENEFIT. The term "Accrued Benefit" shall mean the Normal
Retirement Benefit (before applying the offsets in clauses (1), (2), (3), and
(4) of Section 2.1 above) to which the Executive would be entitled under Section
2.1 commencing at the Normal Retirement Date assuming continuation of the
Executive's employment with the Corporation until the Normal Retirement Date
based on the Benefit Computation Base on the date the Accrued Benefit is
determined, multiplied by a fraction not to exceed one (1), the numerator of
which is the actual number of months of the Executive's employment with the
Corporation (including partial months for month of hire and month of
termination) plus sixty-six (66) and the denominator of which is three hundred
(300) months, and reduced by:

     (1) fifty percent (50%) of the Executive's Primary Social Security
     retirement benefit estimated as of the Normal Retirement Date based on the
     Social Security retirement benefit formulas assuming level future earnings
     based on his Benefit Computation Base in effect on the date of termination
     of the Executive;

     (2) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, from the Pension
     Plan;

     (3) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, which is the
     actuarial equivalent, at the date of determination of the Accrued Benefit,
     of that portion of the Executive's account balances attributable to
     contributions by the Corporation to any and all qualified defined
     contribution plans maintained by the Corporation; and

     (4) the annual amount of benefits payable to the Executive, stated as a
     life annuity commencing at the Normal Retirement Date, attributable to
     contributions by the Corporation (but not any amounts attributable to
     deferrals or contributions by the Executive) from any other qualified or
     non-qualified retirement plan or agreement maintained or entered into by
     the Corporation.

SECTION 2.4 OPTIONAL FORMS OF PAYMENT. In lieu of the fifteen-year certain
payments described in Section 2.1 above (payments made over a fifteen-year
period as described in Section 2.1 above are hereinafter referred to as payments
made in the "Normal Form"), or whenever an Accrued Benefit is payable under this
Agreement, the Executive may elect, at any time prior to the calendar year in
which payments are to begin, an optional form of payment which shall be the
actuarial equivalent of payments that would otherwise be made in the Normal
Form, and which shall be (x) any optional form which is made available to the
Executive under the terms of the Pension Plan or (y) a single lump sum payment.

SECTION 2.5 VESTING. The Executive, having completed more than five (5) years of
employment with the Corporation, has a vested interest in the Accrued Benefit
payable under this Agreement.

                                  ARTICLE THREE

SECTION 3.1 BENEFICIARY. In the event of the death of the Executive, any
payments to be made hereunder after the date of his death ("Remaining Payments")
shall be made to the Executive's

                                       3
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Beneficiary, as defined below, and in such case all references to "Executive"
herein shall, where applicable, apply to the Beneficiary. The Executive may name
one or more beneficiaries (each, a "Beneficiary") in writing to the Corporation.
If no Beneficiary is so named or if no named Beneficiary is living at the time a
payment is due, that payment and all subsequent payments shall be made, when
otherwise due, to the Executive's estate, which shall be the "Beneficiary" for
purposes of this Agreement.

                                  ARTICLE FOUR

SECTION 4.1 DISABILITY PRIOR TO RETIREMENT. No disability benefits will be paid
under this Agreement. If the Executive's employment is terminated or suspended
by reason of mental or physical disability, disability benefits may be paid to
the Executive pursuant to insurance provided by the Corporation pursuant to a
separate policy, plan or agreement. Upon the later of (x) termination of any
such other disability benefits or (y) the Normal Retirement Date, payment to the
Executive of his Accrued Benefit (determined as of the date of disability) shall
commence and such payment shall be made in the form provided in Section 2.4. If,
following termination or suspension of the Executive's employment by reason of
disability, the Executive resumes employment with the Corporation in the
position he held immediately prior to the onset of disability, this Agreement
shall continue in full force and effect as if no such disability or termination
or suspension of employment had occurred. For the purposes of the numerator of
the fractions in Sections 2.1 and 2.3, the Executive's period of disability
shall be treated as a period of employment with the Corporation.

                                  ARTICLE FIVE

SECTION 5.1 TERMINATION OF EMPLOYMENT PRIOR TO NORMAL RETIREMENT DATE. If the
Executive's employment with the Corporation is terminated prior to the Normal
Retirement Date for any reason, the Executive shall be entitled to benefits in
the amount of the Accrued Benefit determined as of the date of termination of
his employment ("Early Retirement Benefits") payable (x) in the Normal Form
commencing at the Normal Retirement Date or (y) to the extent so elected by the
Executive, in any other form permitted under Section 2.4 and commencing at such
other time as may be permitted under Section 5.2 below, subject to such
adjustment as may be provided under Section 5.2 below.

SECTION 5.2 EARLY PAYMENT. By written notice to the Company, the Executive may
elect to have the Corporation commence payment of Early Retirement Benefits at
any time after the Executive has both attained age fifty-five (55) and
terminated employment with the Corporation or at any earlier time for
commencement as the Corporation, in its discretion, may approve. Early
Retirement Benefits shall be in the amount(s) determined in accordance with
Section 5.1, but further reduced (1) by one-quarter of one percent (.25%) per
month for each month or partial month (up to sixty (60)) between the date of
commencement of Early Retirement Benefits and the Executive's sixty-fifth (65th)
birthday and (2) by one-half of one percent (.50%) per month for each month or
partial month between the date of commencement of Early Retirement Benefits and
the date of the Executive's sixtieth (60th) birthday.

SECTION 5.3 PAYMENT. Benefits payable under this Article Five shall be paid in
the Normal Form or in any other manner elected by the Executive and permitted
under Section 2.4.

                                       4
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SECTION 5.4 FORFEITURE. Notwithstanding anything to the contrary herein,
benefits under this Agreement shall be forfeited and all rights of the Executive
and his Beneficiary shall become null and void if the Executive's employment is
terminated for Cause. For the purposes of this Section 5.4, the term "Cause"
shall have the meaning given such term in the William J. Ryan Severance
Agreement dated January 1, 2000.

                                   ARTICLE SIX

SECTION 6.1 ASSIGNMENT. No right to payment of any amount under this Agreement
may be assigned, pledged, or encumbered, nor shall any such right or other
interest in amounts payable under this Agreement be subject to any attachment,
garnishment, execution or other legal process.

                                  ARTICLE SEVEN

SECTION 7.1 PARTICIPATION IN OTHER PLANS. Nothing contained in this Agreement
shall be construed to alter, abridge, or in any manner affect the rights and
privileges of the Executive to participate in and be covered by any pension,
profit-sharing, group insurance, bonus or any other employee plan or plans which
the Corporation may have or hereafter have.

SECTION 7.2 ALTERNATIVE BENEFIT UNDER THE SERP PLAN. Without limiting the
foregoing, and notwithstanding anything to the contrary in the Banknorth Group,
Inc. Supplemental Retirement Plan (as the same may be amended, restated,
otherwise modified or replaced, the "SERP Plan"), including, without limitation,
Article Three thereof, if on the date that benefits become payable under this
Agreement, the actuarial equivalent of the aggregate amount of the benefits
payable to the Executive under the terms of this Agreement is less than the
actuarial equivalent of the aggregate amount of the benefits to which the
Executive would be entitled under the SERP Plan if he were a "Participant" (as
defined in the SERP Plan) in the SERP Plan (such amount, the "Alternative
Benefit"), the Executive shall be entitled to benefits payable in accordance
with the terms of this Agreement but in an aggregate amount equal to the
actuarial equivalent of the Alternative Benefit instead of in an aggregate
benefit amount determined under this Agreement.

                                  ARTICLE EIGHT

SECTION 8.1 FUNDING. The Corporation shall have the right, in its discretion, at
any time and from time to time to insure or otherwise provide for the
obligations of the Corporation under this Agreement or to refrain from same, and
to determine the extent, nature and method thereof, including the establishment
of one or more trusts. Should the Corporation elect to insure this Agreement, in
whole or in part, through the medium of insurance or annuities, or both, the
Corporation shall be the owner and beneficiary of the policy. At no time shall
the Executive be deemed to have any right, title or interest in or to any
specified asset or assets of any such trust or escrow arrangement, including,
without limitation, any insurance or annuity or other contracts or proceeds
therefrom. No such policy, contract or other asset shall in any way be
considered to be security for the performance of the Corporation's obligations
under this Agreement. The Executive agrees that, if the Corporation purchases a
life insurance or annuity policy on his life, he will sign any papers that may
be required for that purpose and undergo any medical

                                       5
<PAGE>

examination or tests which may be necessary, and otherwise reasonably cooperate
with the Corporation in its efforts to secure any such policy.

SECTION 8.2. NO TRUST. Nothing herein and no action taken pursuant hereto shall
create or be deemed to create any trust or fiduciary relationship between the
Corporation and the Executive, his Beneficiary, or any other person.

                                  ARTICLE NINE

SECTION 9.1 REORGANIZATION. The Corporation shall not merge with or consolidate
into or with another corporation or other entity, or reorganize, or sell
substantially all of its assets to another corporation, firm, or person unless
and until such succeeding or continuing corporation, firm or person agrees to
assume and discharge the obligations of the Corporation under this Agreement.
Upon the occurrence of any such merger, consolidation, reorganization, or sale,
the term "Corporation" as used in this Agreement shall be deemed to refer to
such successor, assignee, or survivor or successor Corporation, firm or person.

                                   ARTICLE TEN

SECTION 10.1 BINDING EFFECT. This Agreement shall be binding upon and inure to
the benefit of the Executive and his Beneficiary and the Corporation and any
successor organization which shall succeed to substantially all of its assets
and business without regard to the form of such succession.

SECTION 10.2 CORPORATION. As used in this Agreement, the term "Corporation"
shall mean Banknorth Group, Inc., and any entity that from time to time is
aggregated with Banknorth Group, Inc., its successors and assigns, under
Sections 414(b), 414(c), 414(m), 414(n) or 414(o) of the Internal Revenue Code
of 1986, as amended. For the purpose of determining the Executive's period of
employment with the Corporation as required hereunder, the term "Corporation"
shall also include any predecessor of the Corporation.

                                 ARTICLE ELEVEN

SECTION 11.1. COMMUNICATIONS. Any notice or other communication required or
permitted to be given under this Agreement shall be in writing and shall be
deemed given (i) when delivered or refused if sent by hand during regular
business hours, (ii) three (3) business days after being sent by United States
Postal Service, registered or certified mail, postage prepaid, return receipt
requested, (iii) on the next business day when sent by reputable overnight
express mail service that provides tracing and proof of receipt or refusal of
items mailed, or (iv) when received by the addressee if by telecopier
transmission addressed to the Corporation or Executive, as the case may be, at
the address or addresses set forth below or such other addresses as the parties
may designate in a notice given in accordance with this Section.

To the Corporation:

      Banknorth Group, Inc.
      Two Portland Square
      Portland, ME 04112

                                       6
<PAGE>

To the Executive:

      William J. Ryan
      6 Hemlock Drive
      Cumberland Center, ME 04021

                                 ARTICLE TWELVE

12.1 CLAIMS PROCEDURE GENERALLY. Any claim for benefits under this Agreement
("Claim") shall be made by written notice (x) describing the basis for the Claim
and (y) submitted to the Corporation within six months after the date on which
such benefit is claimed to have been due. Within sixty (60) days after its
receipt of a Claim, the Corporation shall respond to the Executive (or, if
applicable, Beneficiary) by written notice of its determination to approve or
deny the same, which notice, in the case of any denial, shall further set forth
in reasonable detail the basis for denial, specific reference to the Plan
provisions on which the denial is based, steps to be taken to have the denial
reviewed and, if applicable, a description of any additional material needed to
be provided by the Executive. The Executive may, in his discretion, elect to
treat any failure of the Corporation to respond to a Claim within the time
period set forth above as denial.

SECTION 12.2 REVIEW. If a Claim is denied, the Executive may obtain a review of
the denial by written request for review (x) describing the basis for his
determination that denial was erroneous and (y) submitted to the Corporation
within sixty (60) days after the date of denial or deemed denial of the Claim
pursuant to Section 12.1 above, as applicable. Within sixty days (60) following
the Corporation's receipt of a request for review, the Corporation shall review
the Claim (together with any supporting documents or other written materials
reasonably related to the request and submitted therewith) and give the
Executive written notice of its determination to approve or deny the same, which
notice, in the case of any denial, shall further set forth in reasonable detail
the basis for denial. No determination of the Corporation shall be deemed to
preclude further action by the Executive (or, if applicable, Beneficiary) with
respect to the Claim.

                                ARTICLE THIRTEEN

SECTION 13.1 WITHHOLDING. The Corporation shall be entitled to withhold from
payment of benefits hereunder any federal, state or local withholding or other
taxes, or charge from time to time required to be withheld.

                                ARTICLE FOURTEEN

SECTION 14.1 ENTIRE AGREEMENT; AMENDMENT. This Agreement constitutes the entire
agreement between the parties with respect to the subject matter hereof and
supercedes all prior agreements written or oral with respect to its subject
matter. This Agreement may be amended only by a written agreement signed by the
parties hereto.

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<PAGE>

SECTION 14.2 GOVERNING LAW. This Agreement shall be governed by and construed
and enforced in accordance with the laws of the State of Maine.

SECTION 14.3 SEVERABILITY. Each provision of this Agreement is intended to be
severable and the invalidity, illegality, or unenforceability of any portion of
this Agreement shall not affect the validity, legality, and enforceability of
the remainder.

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<PAGE>

     IN WITNESS WHEREOF, the Corporation and the Executive have caused this
Agreement to be executed as an instrument under Seal as of the date and year
first above written.

                                            BANKNORTH GROUP, INC.,
                                            f/k/a PEOPLES HERITAGE FINANCIAL
                                            GROUP, INC.

------------------------------------        By:--------------------------------
Witness                                        Cynthia H. Hamilton, EVP

------------------------------------           ---------------------------------
Witness                                        William J. Ryan

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