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                                                                    Exhibit 3.13


                          CERTIFICATE OF INCORPORATION
                                       OF
                          PSC SERVICES OF FLORIDA, INC.

                                    * * * * *


1.       The name of the corporation is PSC Services of Florida, Inc.

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

3.       The nature of the business or purposes to be conducted or promoted is:

         To engage in any lawful act or activity for which corporations may be
organized under the General Corporation Law of Delaware.

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

         To acquire, and pay for in cash, stock or bonds of this corporation or
otherwise, the good will, rights, assets and property, and to undertake or
assume the whole or any part of the obligations or liabilities of any person,
firm, association or corporation.

         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,
improvements and processes, copyrights, trademarks and trade names, relating to
or useful in connection with any business of this corporation.

         To acquire by purchase, subscription or otherwise, and to receive,
hold, own, guarantee, sell, assign, exchange, transfer, mortgage, pledge or
otherwise dispose of or deal in and with any of the shares of the capital stock,
or any voting trust certificates in respect of the shares of capital stock,
scrip, warrants, rights, bonds, debentures, notes, trust receipts, and other
securities, obligations, choses in action and evidences of indebtedness or
interest issued or created by any corporations, joint stock companies,
syndicates, associations, firms, trusts or persons, public or private, or by the
government of the United States of America, or by any foreign government, or by
any state, territory, province, municipality or other political subdivision or
by any governmental agency, and as owner thereof to possess and exercise all the
rights, powers and privileges of ownership, including the right to execute
consents and vote thereon, and to do any and all acts and things necessary or
advisable for the preservation, protection, improvement and enhancement in value
thereof.


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         To borrow or raise money 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 therein by mortgage upon or pledge, conveyance or assignment in
trust of the whole or any 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.

       To purchase, receive, take by grant gift, devise, bequest or otherwise,
lease, or otherwise acquire, own, hold, improve, employ, use and otherwise deal
in and with real or personal property, or any interest therein, whenever
situated, and to sell, convey, lease, exchange, transfer or otherwise dispose
of, or mortgage or pledge, all or any of the corporation's property and assets,
or any interest therein, wherever situated.

       In general, to possess and exercise all the powers and privileges granted
by the General Corporation Law of Delaware or by any other law of Delaware or by
this Certificate of Incorporation together with any powers incidental thereto,
so far as such powers and privileges are necessary or convenient to the conduct,
promotion or attainment of the business or purposes of the corporation.

       The business 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 business and purposes specified in each of
the foregoing clauses of this article shall be regarded as independent business
and purposes.

4.       The total number of shares of stock which the corporation shall have
authority to issue is One Hundred (100); all of such shares shall be without par
value.

5.       The name and mailing address of each incorporator is as follows:



NAME                                              MAILING ADDRESS
- ----                                              ---------------
                                               
M. A. Brzoska                                     1209 Orange Street
                                                  Wilmington, Delaware  19801
K. A. Widdoes                                     1209 Orange Street
                                                  Wilmington, Delaware  19801
L. J. Vitalo                                      1209 Orange Street
                                                  Wilmington, Delaware  19801


         The name and mailing address of each person, who is to serve as a
director until the first annual meeting of the stockholders or until a successor
is elected and qualified, is as follows:


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NAME                                              MAILING ADDRESS
- ----                                              ---------------
                                               
David R. Parker                                   550 Biltmore Way, Coral Gables, Florida  33137
Thomas C. Highland                                550 Biltmore Way, Coral Gables, Florida  33137
Williams F. Evans                                 550 Biltmore Way, Coral Gables, Florida  33137


6.       The corporation is to have perpetual existence.

7.       Elections of directors need not be by written ballot unless the by-laws
of the corporation shall so provide.

         Meetings of stockholders may be held within or without the State of
Delaware, as the by-laws may 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.

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

8.       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.

9.       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



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violation of law, (iii) under Section 174 of the Delaware General Corporation
Law, or (iv) for any transaction from which the director derived any improper
personal benefit.

       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 this is our act and deed and the facts herein stated are true,
and accordingly have hereunto set our hands this Second day of May, 1996.

                                         /s/ M. A. Brzoska
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                                         /s/ K. A. Widdoes
                                         -----------------


                                         /s/ L. J. Vitalo
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