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                                                                    EXHIBIT 4(f)


                              "ENGLISH TRANSLATION"

             PRIVATE INSTRUMENT FOR DEBT ASSUMPTION, ASSIGNMENT AND
                           TRANSFER No. RI0.13/02-STD

By this present private instrument, as the first of the parties hereto, Ericsson
Telecomunicacoes S.A., a Corporation with headquarters at Rua Maria Prestes Maia
No. 300, 4(0) andar, in the City of Sao Paulo, State of Sao Paulo, enrolled at
the CNPJ/MF [General Taxpayer registry of the Ministry of Finances] under No.
33.067.745/0001-27, through its legal representatives below signing, hereinafter
called Contracting Party, and Telepara Celular S.A., as the second of the
Parties hereto, a Corporation with headquarters at Travessa Rui Barbosa 931 -
6(0) andar, in the City of Belem, State of Para, enrolled at the CNPJ/MF under
No. 02.361.554/0001-40, through its legal representatives below signing,
hereinafter called Contracted Party, have agreed upon the terms and conditions
of this Private Instrument for Debt Assumption, Assignment and Transference,
which shall be ruled by the following clauses and conditions:

      12)   The Contracting Party, due to the Private Instrument for Debt
            Assumption, Assignment and Transference No. RI0.13/01-STD, signed on
            September 27th, 2000, became debtor of the Banco Santander Brasil
            S.A., a financial institution with headquarters in the City of Sao
            Paulo, State of Sao Paulo, at Rua Amador Bueno 474, enrolled at the
            CGC/MF under No. 61.472.676/0001-72, [hereinafter called the
            "Creditor" of the amount, in Brazilian currency, equivalent to
            US$10,498,264.32 [ten million, four hundred and ninety eight
            thousand, two hundred and sixty four United States dollars and
            thirty two cents], accrued by financial charges calculated on a base
            of 4.15% [four point fifteen percent] per year over the LIBOR for 06
            [six] months deposits, readjustable half-yearly, falling upon the
            debtor balance of the principal from September 27th, 2000 on, the
            financial charges having to be paid half-yearly, and the principal
            on the maturity, i.e. September 12th, 2003, and shall fall upon the
            interests, income tax calculated at the rate of 15% [fifteen per
            cent], considering that for the calculation of the Income Tax, it
            shall be calculated on the base of 1.75% p.a. [one point seventy
            five per cent] per year, over the LIBOR for 6 months deposits, and
            that the exchange closing shall be made always 02 [two] working days
            prior the maturity of each installment of the financial charges and
            of the principal, as below:

<TABLE>
<CAPTION>
                    ---------------------------------------------------------
                    INSTALLMENT          MATURITY DATE           PAYMENT DATE
                    ---------------------------------------------------------
<S>                                      <C>                     <C>
                         1                 03/26/2001             03/22/2001
                    ---------------------------------------------------------
                         2                 09/24/2001             09/20/2001
                    ---------------------------------------------------------
                         3                 03/22/2002             03/20/2002
                    ---------------------------------------------------------
                         4                 09/17/2002             09/13/3002
                    ---------------------------------------------------------
                         5                 03/18/2003             03/14/2003
                    ---------------------------------------------------------
                         6                 09/12/2003             09/10/2003
                    ---------------------------------------------------------
                     PRINCIPAL             09/12/2003             09/10/2003
                    ---------------------------------------------------------
</TABLE>

      13)   The Contracting Party, through this instrument, transfers to the
            Contracted Party which, by its turn accepts and assumes in this act
            the debt described in Item 1 above, which shall be paid-off by the
            Contracted Party to the Creditor, in the amount equivalent in
            Brazilian currency, to US$ 10,498,264.32 [ten million, four hundred
            and ninety eight thousand, two hundred and sixty four United States
            dollars and thirty two cents], plus all financial charges falling
            upon, observing the dispositions of Clause 5.2 of the Private
            Instrument for Debt Assumption, Assignment and Transference No.
            RI0.13/01.

      13.1) The Creditor appears before this instrument to declare that he is
            aware and agrees with the Transference now made.

      13.2) The Contracted Party assumes, from now on, any increases of the
            Income Tax which may accrue upon the remittance of interests abroad,
            and any contributions, even being provisional, as well as


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            any tributes, taxes, contributions, deposits of any kind, fees or
            other tax impositions and expenses which fall upon or which may fall
            upon on any payments to be made to the Creditor and to the Foreign
            Creditors.

      14)   For the debt assumption now contracted, the Contracting Party is
            paying in this act, to the Contracted Party, the amount of
            R$19,428,087.95 [nineteen million, four hundred and twenty eight
            thousand, and eighty seven Reais and ninety five centavos],
            equivalent on this date to US$ 10,498,264.32 [ten million, four
            hundred and ninety eight thousand, two hundred and sixty four United
            States dollars and thirty two cents].

      15)   The Contracted Party agrees, from now on, that the settlement of the
            debt before the Creditor shall be executed by the Contracting Party,
            nominated in this act as Attorney-in-Fact for such purpose. On the
            other hand the Contracted Party obliges itself to deliver to the
            Contracting Party, which obliges itself also to receive, in the
            respective "Payment Dates" stipulated in Clause 1 of this Contract
            [hereinafter called "Settlement Date"] the equivalent in Brazilian
            currency of the amount of the debt [hereinafter called "Equivalent
            Amount"], amount which shall be obtained at the exchange closing
            date by the corresponding US dollar rate applicable to the Financing
            Contract for the Import of Tangible Goods Number 01.51.00000201.

      16)   The obligations of the Contracting Party derived from this contract
            shall be considered definitively accomplished by the deliver to the
            Banco Santander Brasil S.A. of the following:

                  a)       The funds mentioned in Clause 3; and

                  b)       The necessary documentation so the Contracted Party
                           may comply with its assumed obligations, which the
                           Parties hereto accept and agree to be the described
                           in Annex 1.

      16.1) The Parties shall take all the necessary steps, and sign any
            requested documents in order to allow the remittance of the funds
            abroad ["Equivalent Amount"];

      16.2) The Contracted Party shall exempt the Contracting Party of any
            responsibility related to the risk of exchange and transference of
            the "Equivalent Amount" abroad, this risk being the entire
            responsibility of the Contracted Party.

      17)   The Contracting Party answers, for all legal purposes, for the
            existence and correct formalization of the assumed debt before the
            Original Creditor, exempting, therefore, the Contracted Party of any
            responsibility related to the validity and existence of the debt.

      18)   As a guarantee for the obligations assumed in this present
            instrument, the Contracted Party issues and delivers, in this act,
            to the Creditor, 01 [one] Promissory Note in the amount of
            US$12,601,461.48 [twelve million, six hundred and one thousand, four
            hundred and sixty one US dollars and forty eight cents], with
            maturity on September 12th, 2003.

      19)   All communications between the Parties, or the notices related to
            this present instrument shall be written and delivered personally or
            sent by registered mail, pre-paid postage, or by telex, telegram,
            fax cablegram, to the address of the addressee, indicated for such
            purpose in the preamble of this instrument. All communications shall
            be valid from the date of their deliver.

      20)   The Contracted Party cannot cede or transfer, in its totality or
            part, the compromises and obligations derived from this instrument,
            without the concurrence of the Creditor.

      21)   This present instrument is executed in an irrevocable and
            unchangeable form, obliging all Parties and their successors.

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      22)   The Brazilian laws shall rule this contract. The Parties hereto
            elect the Central Venue of the City of Sao Paulo, State of Sao
            Paulo, as being the competent venue to solve any divergences derived
            from this Instrument. The Party obliging the other one to use the
            legal ways to enforce its rights shall be responsible for the
            payment of the lawyer's fees, besides the judicial costs and
            expenses.

And having agreed upon, the Parties sign this present instrument in 03 [three]
copies with the same tenor and form, for this sole purpose, in the presence of
the witnesses below signing.

Sao Paulo, September 27th, 2000


Ericsson Telecomunicacoes S.A


Telepara Celular S.A.


Banco Santander Brasil S.A.


Guarantor:


Tele Norte Participacoes S.A.


Witnesses


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 ANNEX I TO THE PRIVATE INSTRUMENT FOR DEBT ASSUMPTION, ASSIGNMENT AND TRANSFER
                                  No. RI0.13/02

As stipulated in Item "b" of Clause 5 of the Instrument above mentioned, the
Contracting Party obliges itself to deliver to the Banco Santander Brasil S.A.
the documents below:

      1)    The foreign exchange purchase documents by the remittance of the
            amounts abroad, in accordance with the legislation in force;

      2)    Legalized copy of the Articles of Incorporation or Statute of the
            Contracting Party and the minutes of the General Meeting, which
            elected the Board of Directors, now in office, of the Contracted
            Party.

CONTRATO/RIO 13/02-STD

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