Exhibit 3.13

                                                         STATE OF DELAWARE
                                                         SECRETARY OF STATE
                                                      DIVISION OF CORPORATIONS
                                                      FILED 09:00 AM 12/31/1998
                                                          981510676 - 2403650


                            CERTIFICATE OF AMENDMENT
                                     OF THE
                          CERTIFICATE OF INCORPORATION
                                       OF
                           GILRO CELLULAR CORPORATION


         Gilro Cellular Corporation, a corporation duly organized and existing
under the General Corporation Law of the State of Delaware (the "Corporation"),
does hereby certify that:

         1.   The amendment to the Corporation's Certificate of Incorporation
set forth below was duly adopted in accordance with the provisions of Section
242 and has been consented to in writing by the sole stockholder, in
accordance with Section 228 of the General Corporation Law of the State of
Delaware.

         2.   ARTICLE I of the Corporation's Certificate of Incorporation, which
sets forth the name of the Corporation is hereby amended to read in its entirety
as follows:

         ARTICLE I:  The name of the Corporation is ACC of Michigan Corporation.

         IN WITNESS WHEREOF, Gilro Cellular Corporation has caused this
Certificate to be executed by its duly authorized officer on this 31st day of
December, 1998.


                                       GILRO CELLULAR CORPORATION




                                       By: /s/ JOHN FUJII
                                          ---------------------------------
                                          Name:  John Fujii
                                          Title: Chief Executive Officer





                          CERTIFICATE OF INCORPORATION

                                       OF

                           GILRO CELLULAR CORPORATION



         I, the undersigned, for the purpose of incorporating and organizing
a corporation under the General Corporation Law of the State of Delaware, do
hereby execute this Certificate of Incorporation and do hereby certify as
follows:

                                    ARTICLE I

         The name of the corporation (which is hereinafter referred to as the
"Corporation") is:


                            Gilro Cellular Corporation


                                   ARTICLE II

         The address of the Corporation's registered office in the State of
Delaware is The Corporation Trust Center, 1209 Orange Street in the City of
Wilmington, County of New Castle.  The name of the Corporation's registered
agent at such address is The Corporation Trust Company.

                                   ARTICLE III

         The purpose of the Corporation shall be to engage in any lawful act or
activity for which corporations may be organized and incorporated under the
General Corporation Law of the State of Delaware.




                                   ARTICLE IV

         Section 1. The Corporation shall be authorized to issue 100 shares
of capital stock, all of which 100 shares shall be shares of Common Stock,
$.01 par value ("Common stock").

         Section 2. Except as otherwise provided by law, the Common Stock
shall have the exclusive right to vote for the election of directors and for
all other purposes. Each share of Common Stock shall have one vote, and the
Common Stock shall vote together as a single class.

                                    ARTICLE V

         Unless and except to the extent that the By-Laws of the Corporation
shall so require, the election of directors or the Corporation need not be by
written ballot.

                                   ARTICLE VI

         In furtherance and not in limitation or the powers conferred by law,
the Board of Directors of the Corporation (the "Board") is expressly authorized
and empowered to make, alter and repeal the By-Laws of the Corporation by a
majority vote at any regular or special meeting of the Board or by written
consent, subject to the power of the stockholders or Corporation to alter or
repeal any By-Laws made by the Board.


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                                   ARTICLE VII

         The Corporation reserves the right at any time from time to time to
amend, alter, change or repeal any provision contained in this Certificate of
Incorporation, and any other provisions authorized by the laws of the State of
Delaware at the time in force may be added or inserted, in the manner now or
hereafter prescribed by law; and all rights, preferences and privileges of
whatsoever nature conferred upon stockholders, directors or any other persons
whomsoever by and pursuant to this Certificate of Incorporation in its present
form or as hereafter amended are granted subject to the right reserved in this
Article.

                                   ARTICLE VIII

         Section 1.  ELIMINATION OF CERTAIN LIABILITY OF DIRECTORS. A
director of the Corporation shall not be personally liable to the Corporation
or its stockholders for monetary damages for breach of fiduciary duty as a
director, except for liability (i) for any breach of the director's duty of
loyalty to the Corporation or its stockholders, (ii) for acts or omissions
not in good faith or which involve intentional misconduct or a knowing
violation or law, (iii) under Section 174 of the General Corporation Law of
the State or Delaware, or (iv) for any transaction from which the director
derived an improper personal benefit.


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         Section 2.  INDEMNIFICATION AND INSURANCE.

         (a)  RIGHT TO INDEMNIFICATION. Each person who was or is made a party
or is threatened to be made a party to or is involved in any action, suit or
proceeding, whether civil, criminal, administrative or investigative
(hereinafter a "proceeding"), by reason of the fact that he or she, or a person
of whom he or she is the legal representative, is or was a director or officer
of the Corporation or is or was serving at the request of the Corporation as a
director, officer, employee or agent of another corporation or of a partnership,
joint venture, trust or other enterprise, including Service with respect to
employee benefit plans, whether the basis of such proceeding is alleged action
in an official capacity as a director, officer, employee or agent or in any
other capacity while serving as a director, officer, employee or agent, shall be
indemnified and held harmless by the Corporation to the fullest extent
authorized by the General Corporation Law of the State of Delaware, as the same
exists or may hereafter be amended (but, in the case of any such amendment, only
to the extent that such amendment permits the Corporation to provide broader
indemnification rights than said law permitted the Corporation to provide prior
to such amendment), against all expense, liabilIty and loss (including
attorneys' fees, judgments, fines, amounts paid or to be paid in settlement, and
excise taxes or penalties arising under


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the Employee Retirement Income Security Act of 1974) reasonably incurred or
suffered by such person in connection therewith and such indemnification
shall continue as to a person who has ceased to be a director, officer,
employee or agent and shall inure to the benefit of his or her heirs,
executors and administrators; PROVIDED, HOWEVER, that, except as provided in
paragraph (b) hereof, the Corporation shall indemnify any such person seeking
indemnification in connection with a proceeding (or part thereof) initiated
by such person only if such proceeding (or part thereof) was authorized by
the Board. The right to indemnification conferred in this Section shall be a
contract right and shall include the right to be paid by the Corporation the
expenses incurred in defending any such proceeding in advance of its final
disposition; PROVIDED, HOWEVER, that, if the General Corporation Law or the
State of Delaware requires, the payment of such expenses incurred by a
director or officer in his or her capacity as a director or officer (and not
in any other capacity in which service was or is rendered by such person
while a director or officer, including, without limitation, service to an
employee benefit plan) in advance of the final disposition of a proceeding,
shall be made only upon delivery to the Corporation of an undertaking, by or
on behalf of such director or officer, to repay all amounts so advanced if it
shall ultimately be determined that such director or officer is not entitled
to be indemnified under this Section or otherwise.


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The Corporation may, by action of the Board, provide indemnification to
employees and agents of the Corporation with the same scope and effect as the
foregoing indemnification of directors and officers.

         (b)  RIGHT OF CLAIMANT TO BRING SUIT. If a claim under paragraph (a) of
this Section is not paid in full by the Corporation within thirty days after a
written claim has been received by the Corporation, the claimant may at any time
thereafter bring suit against the Corporation to recover the unpaid amount of
the claim and, if successful in whole or in part, the claimant shall be entitled
to be paid also the expense of prosecuting such claim. It shall be a defense to
any such action (other than an action brought to enforce a claim or expenses
incurred in defending any proceeding in advance of its final dispositIon where
the required understanding, if any is required, has been tendered to the
Corporation) that the claimant has not met the standards of conduct which make
it permissible under the General Corporation Law or the State of Delaware for
the Corporation to indemnify the claimant for the amount claimed, but the burden
of proving such defense shall be on the Corporation. Neither the failure of the
Corporation (including its Board, independent legal counsel, or its
stockholders) to have made a determination prior to the commencement of such
action that indemnification of the claimant is proper in the circumstances
because he or she has met the applicable standard of conduct set


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forth in the General Corporation Law of the State of Delaware, nor an actual
determination by the Corporation (including its Board, independent legal
counsel, or its stockholders) that the claimant has not met such applicable
standard of conduct, shall be a defense to the action or create a presumption
that the claimant has not met the applicable standard of conduct.

         (c)  NON-EXCLUSIVITY OF RIGHTS.  The right to indemnification and
the payment of expenses incurred in defending a proceeding in advance of its
final disposition conferred in this Section shall not be exclusive of any
other right which any person may have or hereafter acquire under any statute,
provision of the Certificate of Incorporation, By-Law, agreement, vote of
stockholders or disinterested directors or otherwise.

         (d)  INSURANCE.  The Corporation may maintain insurance, at its
expense, to protect itself and any director, officer, employee or agent of
the Corporation or another corporation, partnership, joint venture, trust or
other enterprise against any such expense, liability or loss, whether or not
the Corporation would have the power to indemnify such person against such
expense, liability or loss under the General Corporation Law of the State of
Delaware.


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                                   ARTICLE IX

         The name and mailing address of the incorporator is Andrew J. Nussbaum,
Esq., c/o Wachtell, Lipton, Rosen & Katz, 51 West 52nd Street, New York, New
York 10019.

         IN WITNESS WHEREOF, I, the undersigned, being the incorporator
hereinbefore named, do hereby further certify that the facts hereinabove stated
are truly set forth and, accordingly, I have hereunto set my hand this 18 day
of May, 1994.


                                       /s/ ANDREW J. NUSSBAUM
                                       --------------------------------
                                       Andrew J. Nussbaum
                                       Incorporator









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