EXHIBIT 3.19


                                                               STATE OF DELAWARE
                                                              SECRETARY OF STATE
                                                        DIVISION OF CORPORATIONS
                                                       FILED 09:00 AM 08/07/1990
                                                             750219077 - 2238135

                          CERTIFICATE OF INCORPORATION

                                       OF

                          W. W. INVENTORY SERVICE CORP.

                                 _______________

            The undersigned, a natural person, for the purpose of organizing a
corporation for conducting the business and promoting the purposes hereinafter
stated, under the provisions and subject to the requirements of the laws of the
State of Delaware (particularly Chapter 1, Title 8 of the Delaware Code and the
acts amendatory thereof and supplemental thereto, and known, identified and
referred to as the "General Corporation Law of the State of Delaware"), hereby
certifies that:

            FIRST: The name of the corporation (hereinafter called the
"corporation") is

                          W. W. INVENTORY SERVICE CORP.

            SECOND: The address, including street, number, city, and county, of
the registered office of the corporation in the State of Delaware is 32
Loockerman Square, Suite L-100, City of Dover, County of Kent; and the name of
the registered agent of the corporation in the State of Delaware is The
Prentice-Hall Corporation System, Inc.

            THIRD: The nature of the business and of the purposes to be
conducted and promoted by the corporation, which shall be in addition to the
authority of the corporation to conduct any lawful business, to promote any
lawful purpose, and to engage in any lawful act or activity for which
corporations may be organized under the General Corporation Law of the State of
Delaware, is as follows:

            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, wherever situated, and to sell, convey, lease, exchange, transfer
      or otherwise dispose of, or mortgage or pledge, all or any of its property
      and assets, or any interest therein, wherever situated.

            To engage generally in the real estate business as principal, agent,
      broker, and in any lawful capacity, and generally to take, lease,
      purchase, or otherwise acquire, and to own, use, hold, sell, convey,
      exchange, lease, mortgage, work, clear, improve, develop, divide, and
      otherwise handle, manage, operate, deal in and dispose of real estate,
      real property, lands,


      multiple-dwelling structures, houses, buildings and other works and any
      interest or right therein; to take, lease, purchase or otherwise acquire,
      and to own, use, hold, sell, convey, exchange, hire, lease, pledge,
      mortgage, and otherwise handle, and deal in and dispose of, as principal,
      agent, broker, and in any lawful capacity such personal property,
      chattels, chattels real, rights, easements, privileges, choses in action,
      notes, bonds, mortgages, and securities as may lawfully be acquired, held,
      or disposed of; and to acquire, purchase, sell, assign, transfer, dispose
      of, and generally deal in and with as principal, agent, broker, and in any
      lawful capacity, mortgages and other interests in real, personal, and
      mixed properties; to carry on a general construction, contracting,
      building, and realty management business as principal agent,
      representative, contractor, subcontractor, and in any other lawful
      capacity.

            To carry on a general mercantile, industrial, investing, and trading
      business in all its branches; to devise, invent, manufacture, fabricate,
      assemble, install, service, maintain, alter, buy, sell, import, export,
      license as licensor or licensee, lease as lessor or lessee, distribute,
      job enter into, negotiate, execute, acquire, and assign contracts in
      respect of, acquire, receive grant, and assign licensing arrangements,
      options, franchises, and other rights in respect of, and generally deal in
      and with, at wholesale and retail, as principal, and as sales, business,
      special, or general agent, representative, broker, factor, merchant,
      distributor, jobber, advisor, and in any other lawful capacity, goods,
      wares, merchandise, commodities, and unimproved, improved, finished,
      processed, and other real, personal, and mixed property of any and all
      kinds, together with the components, resultants, and by-products thereof.

            To apply for, register, obtain, purchase, lease, take licenses in
      respect of or otherwise acquire, and to hold, own, use, operate, develop,
      enjoy, turn to account, grant licenses and immunities in respect of,
      manufacture under and to introduce, sell, assign, mortgage, pledge or
      otherwise dispose of, and, in any manner deal with and contract with
      reference to:

                  (a) inventions, devices, formulae, processes and any
            improvements and modifications thereof;

                  (b) letters patent, patent rights, patented processes,
            copyrights, designs and similar rights, trade-marks, trade names,
            trade symbols and other indications of origin and ownership granted
            by or recognized under the laws of the United States of America, the
            District of Columbia, any state or subdivision thereof, and any
            commonwealth, territory, possession, dependency, colony, possession,
            agency or instrumentality of the United States of America and of any
            foreign country, and all rights connected therewith or appertaining
            thereunto;

                  (c) franchises, licenses, grants and concessions.

            To guarantee, purchase, take, receive, subscribe for, and otherwise
      acquire, own, hold, use, and otherwise employ, sell, lease, exchange,
      transfer, and otherwise dispose of, mortgage, lend, pledge, and otherwise
      deal in and with, securities (which term for the purpose of this


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      Article THIRD, includes without limitation of the generality thereof, and
      shares of stock, bonds, debentures, notes, mortgages, other obligations,
      and any certificates, receipts or other instruments representing rights to
      receive, purchase or subscribe for the same, or representing any other
      rights or interests therein or in any property or assets) of any persons,
      domestic and foreign firms, associations, and corporations, and by any
      government or agency or instrumentality thereof; to make payment therefor
      in any lawful manner; and, while owner of any such securities, to exercise
      any and all rights, powers and privileges in respect thereof, including
      the right to vote.

            To make, enter into, perform and carry out contracts of every kind
      and description with any person, firm, association, corporation or
      government or agency or instrumentality thereof.

            To acquire by purchase, exchange or otherwise, all, or any part of,
      or any interest in, the properties, assets, business and good will of any
      one or more persons, firms, associations or corporations heretofore or
      hereafter engaged in any business for which a corporation may now or
      hereafter be organized under the laws of the State of Delaware; to pay for
      the same in cash, property or its own or other securities; to hold,
      operate, reorganize, liquidate, sell or in any manner dispose of the whole
      or any part thereof; and in connection therewith, to assume or guarantee
      performance of any liabilities, obligations or contracts of such persons,
      firms, associations or corporations, and to conduct the whole or any part
      of any business thus acquired.

            To lend money in furtherance of its corporate purposes and to invest
      and reinvest its funds from time to time to such extent, to such persons,
      firms, associations, corporations, governments or agencies or
      instrumentalities thereof, and on such terms and on such security, if any,
      as the Board of Directors of the corporation may determine.

            To make contracts of guaranty and suretyship of all kinds and
      endorse or guarantee the payment of principal, interest, or dividends
      upon, and to guarantee the performance of sinking fund or other
      obligations of, any securities, and to guarantee in any way permitted by
      law the performance of any of the contracts or other undertakings in which
      the corporation may otherwise be or become interested, of any persons,
      firm, association, corporation, government or agency or instrumentality
      thereof, or of any other combination, organization or entity whatsoever.

            To borrow money without limit as to amount and at such rates of
      interest as it may determine; from time to time to issue and sell its own
      securities, including its shares of stock, notes, bonds, debentures, and
      other obligations, in such amounts, on such terms and conditions, for such
      purposes and for such prices, now or hereafter permitted by the laws of
      the State of Delaware and by this certificate of incorporation, as the
      Board of Directors of the corporation may determine; and to secure any of
      its obligations by mortgage, pledge or other encumbrance of all or any of
      its property, franchises and income.


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            To be a promoter or manager of other corporations of any type or
      kind; and to participate with others in any corporation, partnership,
      limited partnership, joint venture, or other association of any kind, or
      in any transaction, undertaking or arrangement which the corporation would
      have power to conduct by itself, whether or not such participation
      involves sharing or delegation of control with or to others.

            To draw, make, accept, endorse, discount, execute, and issue
      promissory notes, drafts, bills of exchange, warrants, bonds, debentures,
      and other negotiable or transferable instruments and evidences or
      indebtedness whether secured by mortgage or otherwise, as well as to
      secure the same by mortgage or otherwise, so far as may be permitted by
      the laws of the State of Delaware.

            To purchase, receive, take, reacquire or otherwise acquire, own and
      hold, sell, lend, exchange, reissue, transfer or otherwise dispose of,
      pledge, use, cancel, and otherwise deal in and with its own shares and its
      other securities from time to time to such an extent and in such manner
      and upon such terms as the Board of Directors of the corporation shall
      determine; provided that the corporation shall not use its funds or
      property for the purchase of its own shares of capital stock when its
      capital is impaired or when such use would cause any impairment of its
      capital, except to the extent permitted by law.

            To organize, as an incorporator, or cause to be organized under the
      laws of the State of Delaware, or of any other State of the United States
      of America, or of the District of Columbia, or of any commonwealth,
      territory, dependency, colony, possession, agency, or instrumentality of
      the United States of America, or of any foreign country, a corporation or
      corporations for the purpose of conducting and promoting any business or
      purpose for which corporations may be 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 conduct its business, promote its purposes, and carry on its
      operations in any and all of its branches and maintain offices both within
      and without the State of Delaware, in any and all States of the United
      States of America, in the District of Columbia, and in any or all
      commonwealths, territories, dependencies, colonies, possessions, agencies,
      or instrumentalities of the United States of America and of foreign
      governments.

            To promote and exercise all or any part of the foregoing purposes
      and powers in any and all parts of the world, and to conduct its business
      in all or any of its branches as principal, agent, broker, factor,
      contractor, and in any other lawful capacity, either alone or through or
      in conjunction with any corporations, associations, partnerships, firms,
      trustees, syndicates, individuals, organizations, and other entities in
      any part of the world, and, in conducting its business and promoting any
      of its purposes, to maintain offices, branches and agencies in any part of
      the world, to make and perform any contracts and to do any acts and
      things, and to carry on any business, and to exercise any powers and
      privileges suitable, convenient, or


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      proper for the conduct, promotion, and attainment of any of the business
      and purposes herein specified or which at any time may be incidental
      thereto or may appear conducive to or expedient for the accomplishment of
      any of such business and purposes and which might be engaged in or carried
      on by a corporation incorporated or organized under the General
      Corporation Law of the State of Delaware, and to have and exercise all of
      the powers conferred by the laws of the State of Delaware upon
      corporations incorporated or organized under the General Corporation Law
      of the State of Delaware.

            The foregoing provisions of this Article THIRD shall be construed
both as purposes and powers and each as an independent purpose and power. The
foregoing enumeration of specific purposes and powers shall not be held to limit
or restrict in any manner the purposes and powers of the corporation, and the
purposes and powers herein specified shall, except when otherwise provided in
this Article THIRD, be in no wise limited or restricted by reference to, or
inference from, the terms of any provision of this or any other Article of this
certificate of incorporation; provided, that the corporation shall not conduct
any business, promote any purpose, or exercise any power or privilege within or
without the State of Delaware which, under the laws thereof, the corporation may
not lawfully conduct, promote or exercise.

            FOURTH: The total number of shares of stock which the corporation
shall have authority to issue os One Thousand (1,000). The par value of each of
such shares is One Dollar ($1.00). All such shares are of one class and are
shares of Common Stock.

            FIFTH: The name and the mailing address of the incorporator are as
follows:

            NAME                       MAILING ADDRESS
            ----                       ---------------
            T. M. Bonovich      32 Loockerman Square, Suite L-100
                                Dover, Delaware  19901

            SIXTH: The corporation is to have perpetual existence.

            SEVENTH: 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 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,


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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.

            EIGHTH: For the management of the business and for the conduct of
the affairs of the corporation, and in further definition, limitation and
regulation of the powers of the corporation and of its directors and of its
stockholders or any class thereof, as the case may be, it is further provided:

            1. The management of the business and the conduct of the affairs of
      the corporation shall be vested in its Board of Directors. The number of
      directors which shall constitute the whole Board of Directors shall be
      fixed by, or in the manner provided in, the By-Laws. The phrase "whole
      Board" and the phrase "total number of directors" shall be deemed to have
      the same meaning, to wit, the total number of directors which the
      corporation would have if there were no vacancies. No election of
      directors need be by written ballot.

            2. After the original or other By-Laws of the corporation have been
      adopted, amended, or repealed, as the case may be, in accordance with the
      provisions of Section 109 of the General Corporation Law of the State of
      Delaware, and, after the corporation has received any payment for any of
      its stock, the power to adopt, amend, or repeal the By-Laws of the
      corporation may be exercised by the Board of Directors of the corporation;
      provided, however, that any provision for the classification of directors
      of the corporation for staggered terms pursuant to the provisions of
      subsection (d) of Section 141 of the General Corporation Law of the State
      of Delaware shall be set forth in an initial By-Law or in a By-Law adopted
      by the stockholders entitled to vote of the corporation unless provisions
      for such classification shall be set forth in this certificate of
      incorporation.

            3. Whenever the corporation shall be authorized to issue only one
      class of stock, each outstanding share shall entitle the holder thereof to
      notice of, and the right to vote at, any meeting of stockholders. Whenever
      the corporation shall be authorized to issue more than one class of stock,
      no outstanding share of any class of stock which is denied voting power
      under the provisions of the certificate of incorporation shall entitle the
      holder thereof to the right to vote at any meeting of stockholders except
      as the provisions of paragraph (2) of subsection (b) of section 242 of the
      General Corporation Law of the State of Delaware shall otherwise require;
      provided, that no share of any such class which is otherwise denied voting
      power shall entitle the holder thereof to vote upon the increase or
      decrease in the number of authorized shares of said class.

            NINTH: The personal liability of the directors of the corporation is
hereby eliminated to the fullest extent permitted by paragraph (7) of subsection
(b) of Section 102 of the General Corporation Law of the State of Delaware, as
the same may be amended and supplemented.

            TENTH: The corporation shall, to the fullest extent permitted by
Section 145 of the General Corporation Law of the State of Delaware, as the same
may be amended and supplemented, indemnify any and all persons whom it shall
have power to indemnify under said section from and


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against any and all of the expenses, liabilities or other matters referred to in
or covered by said section, and the indemnification provided for herein shall
not be deemed exclusive of any other rights to which those indemnified may be
entitled under any By-Law, agreement, vote of stockholders or disinterested
directors or otherwise, both as to action in his official capacity and as to
action in another capacity while holding such office, and shall continue as to a
person who has ceased to be a director, officer, employee or agent and shall
inure to the benefit of the heirs, executors and administrators of such a
person.

            ELEVENTH: From time to time any of the provisions of this
certificate of incorporation may be amended, altered or repealed, and other
provisions authorized by the laws of the State of Delaware at the time in force
may be added or inserted in the manner and at the time prescribed by said laws,
and all rights at any time conferred upon the stockholders of the corporation by
this certificate of incorporation are granted subject to the provisions of this
Article ELEVENTH.

Signed on August 7, 1990.

                                        /s/ T.M. Bonovich
                                        -----------------
                                                T. M. Bonovich
                                                Incorporator


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