Exhibit 4(c)

                            CERTIFICATE OF AMENDMENT

                                       OF

                          CERTIFICATE OF INCORPORATION

                                      * * *

          PAN AMERICAN ARGENTINA OIL COMPANY, a corporation organized and
existing under and by virtue of the General Corporation Law of the State of
Delaware, DOES HEREBY CERTIFY:

          FIRST: That the Board of Directors of said corporation, at a meeting
duly convened and held on August 7, 1969, adopted a resolution proposing and
declaring advisable an amendment to the certificate of incorporation of said
corporation, as follows:

          RESOLVED, that it is proposed and declared advisable that the
          Certificate of Incorporation of Pan American Argentina Oil
          Company be amended by striking out all of that Article designated
          "FIRST" and inserting in lieu thereof a new Article "FIRST" to
          read as follows:

               "FIRST.  The name of the corporation is

                    AMOCO ARGENTINA OIL COMPANY"

          SECOND: That the said amendment has been consented to and authorized
by the holder of all the issued and outstanding stock, entitled to vote, by a
written consent given in accordance with the provisions of Section 228 of the
General Corporation Law of the State of Delaware, and filed with the
corporation.

          THIRD: That the aforesaid amendment was duly adopted in accordance
with the applicable provisions of Sections 242 and 228 of the General
Corporation Law of the State of Delaware.

          IN WITNESS WHEREOF, said PAN AMERICAN ARGENTINA OIL COMPANY has caused
its corporate seal to be hereunto affixed and this certificate to be signed by
W. H. Walker, its Vice-President, and Robert H. Frick, its Secretary, on this
19th day of August, 1969.



 PAN AMERICAN ARGENTINA
      OIL COMPANY
    CORPORATE SEAL                  PAN AMERICAN ARGENTINA OIL COMPANY
       DELAWARE
        1958
                                    By   /s/ W. H. Walker
                                         -----------------------------
                                         W. H. Walker, Vice-President


                                    By   /s/ Robert H. Frick
                                        -----------------------------
                                         Robert H. Frick, Secretary


STATE OF ILLINOIS   )
                    )    SS
COUNTY OF COOK      )


          BE IT REMEMBERED that on this 19th day of August, 1969, personally
came before me, the undersigned a notary public of the state aforesaid, W. H.
WALKER, one of the persons signing the foregoing instrument and the
Vice-President of PAN AMERICAN ARGENTINA OIL COMPANY, a corporation of the State
of Delaware, and acknowledged that the said instrument is the act and deed of
the said corporation and that the facts stated therein are true.

          GIVEN under my hand and seal of office the day and year aforesaid.





                                             /s/ Harriet Budniak
                                        ----------------------------------------
                                                  Notary Public



HARRIET BUDNIAK
NOTARY PUBLIC
COOK COUNTY, ILL.


                          CERTIFICATE OF INCORPORATION

                                       OF

                       PAN AMERICAN ARGENTINA OIL COMPANY

          FIRST.  The name of the corporation is

               PAN AMERICAN ARGENTINA OIL COMPANY

          SECOND.  Its principal office in the State of Delaware is located at
No. 100 West Tenth Street, in the City of Wilmington, County of New Castle.  The
name and address of its resident agent is The Corporation Trust Company, No. 100
West Tenth Street, Wilmington 99, Delaware.

          THIRD.  The nature of the business, or objects or purposes to be
transacted, promoted or carried on are:

          To establish and maintain an oil business with authority to contract
for the lease and purchase of the right to prospect for, develop and use coal
and other minerals, petroleum and gas; also the right to erect, build and own
all necessary oil tanks, cars and pipes necessary for the operation of the
business of the same.

          To acquire by purchase, lease or otherwise, and to mortgage, pledge,
lease, sell, or otherwise dispose of, lands and/or the oil, gas and/or mineral
rights in lands for the purpose of producing therefrom oil, gas and/or other
volatile or mineral substances, and to hold, own, develop, operate, dispose of
or in any way use the said lands and/or the oil, gas and/or mineral rights
therein; to develop such lands by and to enter into, acquire, carry out and
execute contracts for, drilling wells and installation of plants, machinery and
appliances, and to dispose of the products therefrom either as a raw product or



otherwise and to refine and reduce and prepare said products for market and to
manufacture from said products any and all marketable commodities.

          To conduct, carry out and perform geological, geophysical and any
other type of exploration of land or water areas for oil, gas, mining and any
other purposes, for itself and for others, and to make, execute, perform and
carry out contracts therefor.

          To drill for, mine for, prepare, process, produce, manufacture,
refine, adapt, buy, sell, distribute and otherwise deal in petroleum and other
oils, vegetable substances, mineral or volatile substances, asphalt, bitumen and
bituminous substances of all kinds, and any and all products, by-products and
residual products therefrom, including the manufacturing, buying, selling and
otherwise dealing in, both wholesale and retail, gasoline and illuminating and
other similar oils; to acquire, sink, own, maintain, operate and develop oil and
gas wells and prepare, adapt, utilize, buy, sell and otherwise deal in and with
the products thereof and therefrom in such manner as may be advantageous or
profitable, and to transact any and all other business pertinent, collateral,
incidental or contributory to any of the purposes aforesaid.

          To manufacture, drill for, mine for, produce, use, and sell artificial
or natural gas, or both, or any mixture of the two, for light, heat, power and
other purposes and also to produce, acquire, use, sell, distribute and treat the
products, by-products and residual products therefrom and to construct or in any
manner acquire, maintain, operate, encumber, sell or in


                                        2


any manner dispose of works therefor; and to transact any and all other business
pertinent, collateral, incidental or contributory to any of the purposes
aforesaid.

          To construct, lay, purchase or in any manner acquire, and to maintain
and operate, and to sell, encumber or in any manner dispose of plants,
refineries, systems, works, appliances, tank structures, equipment, machinery,
pipe-lines, gas mains and buildings and other facilities and equipment, for the
manufacture, treating, concentrating, processing, refining, use, sale,
distribution and transportation of petroleum and other oils, natural and/or
artificial and mixed gas for light, heat, power and other purposes, and their
products, by-products and residual products, in, over, through or under any
streets, alleys, roads, highways or other public places, or in, over, through or
under any private or public property (subject, however, to the consent of
governmental or municipal authorities when the same may be required by law).

          To do a general mining business; to purchase, take, lease or otherwise
acquire, hold, own, control, mine, develop, operate, mortgage, pledge, sell,
transfer, or in any manner dispose of mineral or coal properties, together with
the veins or seams of coal, iron ore or other minerals situated therein and the
works, mining properties, rights or effects connected therewith, and colleries,
smelters and refineries, together with the warehouses, wharves, cars, ships,
vessels, steam boats, or other means of transportation by land or water, stock
in trade, fixed and movable, plants, machinery and other property and


                                        3


effects appurtenant and belonging thereto, and all or any other works or
property held in connection therewith.

          To acquire by purchase or otherwise, hold, own, sell, lease, assign,
transfer, convey, mortgage, encumber and otherwise to deal in and with grants,
franchises, easements, concessions, licenses (including but not limited to oil
exploration licenses and oil prospecting licenses), leases (including but not
limited to oil mining leases), good will, rights and privileges of every kind
and nature, or any interest therein, necessary or incidental in carrying out the
purposes of this corporation and to explore, develop, operate and exploit the
same or to cause or permit the same to be explored, developed, operated or
exploited by others.

          To manufacture, purchase or otherwise acquire, own, mortgage, pledge,
sell, assign and transfer, or otherwise dispose of, to invest, trade, deal in
and deal with, goods, wares, merchandise, commodities, equipment, supplies, and
personal property of every class and description.

          To acquire, hold, use, sell, assign, lease, grant licenses in respect
of, mortgage, or otherwise dispose of letters patent of the United States or any
foreign country, patent rights, licenses and privileges, inventions, formulae,
improvements and processes, copyrights, trade-marks and trade names, relating to
or useful in connection with any business of this corporation.

          To purchase or otherwise acquire the whole or any part of the
property, assets, business, good will and rights and to undertake or assume the
whole or any part of the bonds, mortgages, franchises, leases, contracts,
indebtedness,


                                        4


guaranties, liabilities and obligations of any person, firm, association,
corporation or organization, and to pay for the same or any part or combination
thereof in cash, shares of the capital stock, bonds, debentures, debenture
stock, notes, or other obligations of the corporation or otherwise, or by
undertaking and assuming the whole or any part of the liabilities or obligations
of the transferor; and to hold or in any manner dispose of the whole or any part
of the property and assets so acquired, and to conduct in any lawful manner the
whole or any part of the business so acquired and to exercise all the powers
necessary or convenient in and about the conduct, management and carrying on of
such business.

          To enter into, make, perform and carry out contracts of every kind,
for any lawful purpose, without limit as to amount, with any person, firm,
association or corporation.

          To borrow or raise moneys for any of the purposes of the corporation
and, from time to time, without limit as to amount, to draw, make, accept,
endorse, execute and issue promissory notes, drafts, bills of exchange,
warrants, bonds, debentures and other negotiable or non-negotiable instruments
and evidences of indebtedness, and to secure the payment of any thereof and of
the interest thereon by mortgage upon or pledge, conveyance or assignment in
trust of the whole or any part of the property of the corporation, whether at
the time owned or thereafter acquired, and to sell, pledge or otherwise dispose
of such bonds or other obligations of the corporation for its corporate
purposes.


                                        5


          To purchase, subscribe for, acquire, own, hold, sell, exchange,
assign, transfer, mortgage, pledge or otherwise dispose of shares or voting
trust certificates for shares of the capital stock, or any bonds, notes,
securities or evidences of indebtedness created by any other corporation or
corporations organized under the laws of this state or any other state or
district or country, nation or government and also bonds or evidences of
indebtedness of the United States or of any state, district, territory,
dependency or country or subdivision or municipality thereof; to issue in
exchange therefor shares of the capital stock, bonds, notes or other obligations
of the corporation and while the owner thereof to exercise all the rights,
powers and privileges of ownership including the right to vote on any shares of
stock or voting trust certificates so owned; to promote, lend money to and
guarantee the dividends, stocks, bonds, notes, evidences of indebtedness,
contracts or other obligations of and otherwise aid in any manner which shall be
lawful any corporation or association of which any bonds, stocks, voting trust
certificates, or other securities or evidences of indebtedness shall be held by
or for this corporation or in which, or in the welfare of which, this
corporation shall have any interest, and to do any acts and things permitted by
law and designed to protect, preserve, improve or enhance the value of any such
bonds, stocks or other securities or evidences of indebtedness or the property
of this corporation.

          To organize or cause to be organized under the laws of the State of
Delaware, or of any other state, district,


                                        6


territory, nation, colony, province or government, a corporation or corporations
for the purpose of accomplishing any or all of the objects for which the
corporation is organized, and to dissolve, wind up, liquidate, merge or
consolidate any such corporation or corporations or to cause the same to be
dissolved, wound up, liquidated, merged or consolidated.

          To purchase, hold, sell and transfer the shares of its own capital
stock; provided it shall not use its funds or property for the purchase of its
own shares of capital stock when such use would cause any impairment of its
capital except as otherwise permitted by law, and provided further that shares
of its own capital stock belonging to it shall not be voted upon directly or
indirectly.

          To have one or more offices, to carry on all or any of its operations
and business and without restriction or limit as to amount to purchase or
otherwise acquire, hold, own, mortgage, sell, convey, or otherwise dispose of
real and personal property of every class and description in any of the States,
Districts, Territories or Colonies of the United States, and in any and all
foreign countries, subject to the laws of such State, District, Territory,
Colony or Country.

          In general, to carry on any other business in connection with the
foregoing, and to have and exercise all the powers conferred by the laws of
Delaware upon corporations formed under the act hereinafter referred to, and to
do any or all of the things hereinbefore set forth to the same extent as natural
persons might or could do.


                                        7


          The objects and purposes specified in the foregoing clauses shall,
except where otherwise expressed, be in nowise limited or restricted by
reference to, or inference from, the terms of any other clause in this
certificate of incorporation, but the objects and purposes specified in each of
the foregoing clauses of this article shall be regarded as independent objects
and purposes.

          FOURTH.  The total number of shares of stock which the corporation
shall have authority to issue is Twenty (20) and the par value of each of such
shares is Fifty Thousand Dollars ($50,000.00) amounting in the aggregate to One
Million Dollars ($1,000,000.00).

          FIFTH.  The minimum amount of capital with which the corporation will
commence business is One Thousand Dollars ($1,000.00).

          SIXTH.  The names and places of residence of the incorporators are as
follows:

          NAMES                         RESIDENCES
          -----                         ----------

       H. K. Webb                  Wilmington, Delaware
       H. C. Broadt                Wilmington, Delaware
       A. D. Atwell                Wilmington, Delaware

          SEVENTH.  The corporation is to have perpetual existence.

          EIGHTH.  The private property of the stockholders shall not be subject
to the payment of corporate debts to any extent whatever.


                                        8


          NINTH.  In furtherance and not in limitation of the powers conferred
by statute, the board of directors is expressly authorized;

          To make, alter or repeal the by-laws of the corporation.

          To authorize and cause to be executed mortgages and liens upon the
real and personal property of the corporation.

          To set apart out of any of the funds of the corporation available for
dividends a reserve or reserves for any proper purpose and to abolish any such
reserve in the manner in which it was created.

          By resolution passed by a majority of the whole board, to designate
one or more committees, each committee to consist of two or more of the
directors of the corporation, which, to the extent provided in the resolution or
in the by-laws of the corporation, shall have and may exercise the powers of the
board of directors in the management of the business and affairs of the
corporation, and may authorize the seal of the corporation to be affixed to all
papers which may require it.  Such committee or committees shall have such name
or names as may be stated in the by-laws of the corporation or as may be
determined from time to time by resolution adopted by the board of directors.

          When and as authorized by the affirmative vote of the holders of a
majority of the stock issued and outstanding having voting power given at a
stockholders' meeting duly called for that purpose, or when authorized by the
written consent of the holders of a majority of the voting stock issued and
outstanding, to sell, lease or exchange all of the property and assets of the


                                        9


corporation, including its good will and its corporate franchises, upon such
terms and conditions and for such consideration, which may be in whole or in
part shares of stock in, and/or other securities of, any other corporation or
corporations, as its board of directors shall deem expedient and for the best
interests of the corporation.

          TENTH.  Whenever a compromise or arrangement is proposed between this
corporation and its creditors or any class of them and/or between this
corporation and its stockholders or any class of them, any court of equitable
jurisdiction within the State of Delaware may, on the application in a summary
way of this corporation or of any creditor or stockholder thereof, or on the
application of any receiver or receivers appointed for this corporation under
the provisions of section 291 of Title 8 of the Delaware Code, or on the
application of trustees in dissolution or of any receiver or receivers appointed
for this corporation under the provisions of section 279 of Title 8 of the
Delaware Code, order a meeting of the creditors or class of creditors, and/or of
the stockholders or class of stockholders of this corporation, as the case may
be, to be summoned in such manner as the said court directs.  If a majority in
number representing three-fourths in value of the creditors or class of
creditors, and/or of the stockholders or class of stockholders of this
corporation, as the case may be, agree to any compromise or arrangement and to
any reorganization of this corporation as consequence of such compromise or
arrangement, the said compromise or arrangement and the said reorganization
shall, if sanctioned by the court to which the said application has been


                                       10


made, be binding on all the creditors or class of creditors, and/or on all the
stockholders or class of stockholders, of this corporation, as the case may be,
and also on this corporation.

          ELEVENTH.  Meetings of stockholders may be held outside the State of
Delaware, if the by-laws so provide.  The books of the corporation may be kept
(subject to any provision contained in the statutes) outside the State of
Delaware at such place or places as may be designated from time to time by the
board of directors or in the by-laws of the corporation.  Elections of directors
need not be by ballot unless the by-laws of the corporation shall so provide.

          TWELFTH.  The corporation reserves the right to amend, alter, change
or repeal any provision contained in this certificate of incorporation, in the
manner now or hereafter prescribed by statute, and all rights conferred upon
stockholders herein are granted subject to this reservation.

          WE, THE UNDERSIGNED, being each of the incorporators hereinbefore
named, for the purpose of forming a corporation pursuant to the General
Corporation Law of the State of Delaware, do make this certificate, hereby
declaring and certifying that the facts herein stated are true, and accordingly
have hereunto set our hands and seals this 4th day of September, A. D. 1958.



                                        H. K. WEBB     (SEAL)



                                        H. C. BROADT   (SEAL)



                                        A. D. ATWELL   (SEAL)


                                       11


STATE OF DELAWARE        )

                         )    SS:

COUNTY OF NEW CASTLE     )



          BE IT REMEMBERED that on this 4th day of September, A. D. 1958,
personally came before me, a Notary Public for the State of Delaware, H. K.
Webb, H. C. Broadt and A. D. Atwell, all of the parties to the foregoing
certificate of incorporation, known to me personally to be such, and severally
acknowledged the said certificate to be the act and deed of the signers
respectively and that the facts therein stated are truly set forth.

          GIVEN under my hand and seal of office the day and year aforesaid.



                                        M. Ruth Mannering

                                             Notary Public



M. Ruth Mannering
Notary Public
Appointed Feb. 12, 1957
State of Delaware
Term Two Years


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