EXHIBIT 3.11



                                STATE OF DELAWARE
                                                                          PAGE 1
                        OFFICE OF THE SECRETARY OF STATE

                         ------------------------------

        I, HARRIET SMITH WINDSOR, SECRETARY OF STATE OF THE STATE OF DELAWARE,

DO HEREBY CERTIFY THE ATTACHED IS A TRUE AND CORRECT COPY OF THE CERTIFICATE OF

INCORPORATION OF "TWP" COMPANIES, INC.", FILED IN THIS OFFICE ON THE FIFTEENTH

DAY OF JUNE, A.D. 2001, AT 9 O'CLOCK A.M.













                                       /s/ Harriet Smith Windsor
                                       -----------------------------------------
                 [SEAL]                Harriet Smith Windsor, Secretary of State

                                                        AUTHENTICATION:  1195845

                                                             DATE:  06-18-01




                          CERTIFICATE OF INCORPORATION

                                       OF

                               TWP COMPANIES, INC.



                                   ARTICLE ONE

               The name of the corporation is TWP Companies, Inc.


                                   ARTICLE TWO

               The address of the corporation's registered office in the State
of Delaware is 9 East Lookerman Street, in the City of Dover, County of Kent,
19901. The name of its registered agent at such address is National Registered
Agents, Inc.


                                  ARTICLE THREE

               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 the State of Delaware.


                                  ARTICLE FOUR

               The total number of shares of stock which the corporation has
authority to issue is one thousand (1,000) shares of Common Stock, par value one
cent ($0.01) per share.


                                  ARTICLE FIVE

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




                     NAME                              MAILING ADDRESS
                     ----                              ---------------
                                                
               Thaddine G. Gomez                   200 East Randolph Drive
                                                   Suite 5400
                                                   Chicago, Illinois  60601





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                                   ARTICLE SIX

               The corporation is to have perpetual existence.


                                  ARTICLE SEVEN

               In furtherance and not in limitation of the powers conferred by
statute, the board of directors of the corporation is expressly authorized to
make, alter or repeal the by-laws of the corporation.


                                  ARTICLE EIGHT

               Meetings of stockholders may be held within or without the State
of Delaware, as the by-laws of the corporation may provide. The books of the
corporation may be kept 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. Election of directors need not be by written ballot unless
the by-laws of the corporation so provide.


                                  ARTICLE NINE

               To the fullest extent permitted by the General Corporation Law of
the State of Delaware as the same exists or may hereafter be amended, a director
of this corporation shall not be liable to the corporation or its stockholders
for monetary damages for a breach of fiduciary duty as a director. Any repeal or
modification of this ARTICLE NINE shall not adversely affect any right or
protection of a director of the corporation existing at the time of such repeal
or modification.


                                   ARTICLE TEN

               The corporation expressly elects not to be governed by Section
203 of the General Corporation Law of the State of Delaware.


                                 ARTICLE ELEVEN

               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 herein and by the laws of the State of
Delaware, and all rights conferred upon stockholders herein are granted subject
to this reservation.




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               I, THE UNDERSIGNED, being the sole incorporator 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 my act and deed and the facts stated
herein are true, and accordingly have hereunto set my hand on the 15th day of
June, 2001.



                                            /s/ Thaddine G. Gomez
                                            ---------------------------------
                                            Thaddine G. Gomez
                                            Sole Incorporator




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