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                                                                   Exhibit 10(y)
                                                                  EXECUTION COPY

                               JOINDER AGREEMENT


         Reference is made to the Term Loan Agreement, dated as of July 31, 2000
(as amended, supplemented or otherwise modified from time to time, the "Loan
Agreement"), among GGP Limited Partnership, GGPLP L.L.C., the institutions from
time to time parties thereto as Lenders, Lehman Commercial Paper Inc., as
Syndication Agent, and Bankers Trust Company, as Administrative Agent. Unless
otherwise defined herein, terms defined in the Loan Agreement and used herein
shall have the meanings given to them in the Loan Agreement.

         The Chase Manhattan Bank (the "Joining Lender") (i) represents and
warrants that it is legally authorized to enter into this Joinder Agreement;
(ii) confirms that it has received a copy of the Loan Agreement, together with
copies of such other documents and information as it has deemed appropriate to
make its own credit analysis and decision to enter into this Joinder Agreement;
(iii) agrees that it will, independently and without reliance upon the Co-Agents
or any other Lender and based on such documents and information as it shall deem
appropriate at the time, continue to make its own credit decisions in taking or
not taking action under the Loan Agreement; (iv) appoints and authorizes the Co-
Agents to take such action as agent on its behalf and to exercise such powers
under the Loan Agreement as are delegated to the Co-Agents by the terms thereof,
together with such powers as are reasonably incidental thereto and not otherwise
reserved under the Loan Agreement; (v) agrees that it will perform in accordance
with their terms all of the obligations which by the terms of the Loan Agreement
are required to be performed by it from and after the date hereof as a Lender;
(vi) confirms that, to the best of its knowledge, as of the date hereof, it has
not made any determination which would subject the Borrower to the payment of
additional compensation under Section 13.2 or under Section 13.3 of the Loan
Agreement; (vii) specifies as its Domestic Lending Office (and address for
notices) and Eurodollar Lending Office(s) the offices set forth on Schedule 1
hereto; and (viii) if the Joining Lender is organized under the laws of a
jurisdiction outside the United States, attaches the forms prescribed by the
Internal Revenue Service of the United States certifying as to the Joining
Lender's status for purposes of determining exemption from United States
withholding taxes with respect to all payments to be made to the Joining Lender
under the Loan Agreement and the Notes or such other documents as are necessary
to indicate that all such payments are subject to such taxes at a rate reduced
by an applicable tax treaty.

         Upon execution and delivery of this Joinder Agreement by the parties
hereto as provided in Section 3.2 of the Loan Agreement, (a) the Joining Lender
hereby shall be a party to the Loan Agreement, shall be a Lender under the Loan
Agreement having the Loan Commitments set forth in Schedule 1 hereto, effective
as of the date of this Joinder Agreement, and shall have the rights and
obligations of a Lender under the Loan Agreement and (b) the Maximum Aggregate
Loan Amount shall be increased to $230,000,000.00.

         THIS JOINDER AGREEMENT SHALL BE GOVERNED BY, AND CONSTRUED AND
INTERPRETED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK.
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                                                                               2

         This Joinder Agreement may be executed by one or more of the parties
hereto on any number of separate counterparts, and all of said counterparts
taken together shall be deemed to constitute one and the same instrument.
Delivery of an executed signature page hereof by facsimile transmission shall be
effective as delivery of a manually executed counterpart hereof.
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                                                                               3

         IN WITNESS WHEREOF, the parties hereto have caused this Joinder
Agreement to be duly executed and delivered by their proper and duly authorized
officers as of this 28th day of December, 2000.

                                         THE CHASE MANHATTAN BANK


                                         By:_________________________________
                                            Name:
                                            Title:


Accepted and agreed:

GGP LIMITED PARTNERSHIP, a Delaware limited partnership

By:   GENERAL GROWTH PROPERTIES, INC.,
      a Delaware corporation, its sole general partner

      By: ______________________________
          Name:  Bernard Freibaum
          Title: Executive Vice President

GGPLP L.L.C., a Delaware limited liability company

By:   GGP LIMITED PARTNERSHIP,
      a Delaware limited partnership, its managing member

      By:  GENERAL GROWTH PROPERTIES, INC.,
           a Delaware corporation, its sole general partner

      By: ______________________________
          Name:  Bernard Freibaum
          Title: Executive Vice President
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                                                                               4

Consented to:

BANKERS TRUST COMPANY, as Administrative Agent

By:  ______________________________
     Name:
     Title

LEHMAN COMMERCIAL PAPER INC., as Syndication Agent


By:  ______________________________
     Name:
     Title
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                                                                      Schedule 1


                     LOAN COMMITMENT AND NOTICE ADDRESSES

1.       Name of Lender:                  The Chase Manhattan Bank
         Notice Address and
         Domestic Lending Office:         270 Park Avenue
                                          New York, New York 10017
         Attention:                       Charles Hoagland
         Telephone:                       212-270-9557
         Facsimile:                       212-270-3513

         Eurodollar Lending Office:
                                          270 Park Avenue
                                          New York, New York 10017
         Attention:                       Charles Hoagland
         Telephone:                       212-270-9557
         Facsimile:                       212-270-3513

2.       Loan Commitment:                 $25,000,000.00
         Adjusted Pro Rata Share:         10.87%


                             ADMINISTRATIVE CONTACT

1.       Name of Lender:                  The Chase Manhattan Bank
         Notice Address:                  1 Chase Manhattan Plaza - 8/th/ Floor
                                          New York, New York 10081
         Attention:                       Michael Cerniglia
         Telephone:                       212-552-7906
         Facsimile:                       212-552-5701