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                                                                   Exhibit 10.24

                                                                  EXECUTION COPY


                                NOMINEE AGREEMENT

      THIS NOMINEE AGREEMENT ("AGREEMENT") dated as of the 3rd day of August,
2001, by and between ROBERT MARTIN COMPANY, LLC, a New York limited liability
company ("AGENT") and 5/6 SKYLINE REALTY L.L.C., a New York limited liability
company ("PRINCIPAL").

                                    RECITALS

      A. WHEREAS, pursuant to the Amended and Restated Agreement of Limited
Partnership of Madeira/RMC L.P., dated as of September 1, 1984 (as amended,
the "PARTNERSHIP AGREEMENT"), Agent, Madeira Management Company, Inc.
("MMCI") and Merlot Management Company, Inc. ("MMI" and, together with MMCI,
"MASSERY") continued the existence of a limited partnership under the laws of
the State of New York under the name of Madeira-RMC L.P. (the "PARTNERSHIP")
for the purpose, among others, of owning and developing the real property
located in the Town of Mount Pleasant, County of Westchester, and State of
New York, commonly known as 5 and 6 Skyline Drive in Mid-Westchester
Executive Park and more particularly described on EXHIBIT "A" annexed hereto
and made a part hereof (the "PROPERTY").

      B. WHEREAS, in accordance with the terms of the Partnership Agreement,
Massery has offered to purchase and acquire from Agent all of Agent's right,
title and interest in and to the Partnership (collectively, the "AGENT'S
INTEREST") and Agent has exercised its right to cause Massery to sell, assign,
transfer and convey to Agent all of Massery's right, title and interest in and
to the Partnership (collectively, the "MASSERY Interest");

      C. WHEREAS, Principal wants to acquire the Property to facilitate a
"like-kind" exchange under Section 1031 of the Internal Revenue Code of 1986, as
amended (the "CODE"), subject to the express condition that Principal is able to
acquire the Massery Interest (in the manner described below) and the Agent's
Interest in simultaneous closings;

      D. WHEREAS, Agent neither wishes nor intends to acquire the Massery
Interest for its own account but has agreed to act as Principal's agent in
acquiring the Massery Interest by serving as Principal's nominee for the sole
and limited purpose of acquiring legal title to the Massery Interest for the
sole and absolute benefit of Principal;

      E. WHEREAS, pursuant to the terms of the Partnership Agreement, Massery
has agreed to sell, assign, transfer and convey to Agent, and Agent has agreed
in accordance with this Nominee Agreement to purchase and acquire from Massery
on behalf of Principal (who is solely responsible for funding the acquisition of
the Massery Interest), title to the Massery Interest (the "MASSERY SALE"); and

      F. WHEREAS, pursuant to a Purchase and Sale Agreement between Agent and
Principal, dated August 3, 2001, Agent has agreed to sell its Agent's
Interest and any and all rights therein to Principal and Principal has agreed
to purchase such Interest, subject to the express condition that Principal is
able to acquire the Massery Interest and the Agent's Interest in

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simultaneous closing.

      NOW, THEREFORE, it is hereby agreed as follows:

      1. Principal hereby appoints Agent to act as Principal's nominee for the
sole purpose of taking and holding legal title to the Massery Interest in
Agent's name for Principal's sole and absolute benefit, and Agent hereby accepts
such appointment and agrees to perform such duties for and on behalf of
Principal as are set forth in this Agreement. Agent acknowledges that Agent will
be acquiring the Massery Interest solely as nominee for and on behalf of
Principal. Principal shall have and at all times shall continue to have all
benefits, rights, privileges and liabilities accruing with respect to such
Massery Interest. Agent shall not at any time have any rights, benefits or
burdens of an owner of the Massery Interest (or any interest therein) or any
power to deal with such Massery Interest except as provided in Paragraph 2
below. Agent shall not have any obligation to provide any portion of the
purchase price and other closing costs of the Massery Sale which shall remain
the sole responsibility of Principal, and it is agreed and understood that
Principal shall timely provide and make available to Agent all funds necessary
to enable Agent to complete the closing of the Massery Sale.

      2. Agent shall have no discretionary authority to act for or on behalf of
Principal. Agent shall not do or suffer to be done any act or omission with
respect to the Property or the Massery Interest, but shall perform only such
acts as may be specifically requested by Principal in writing, including,
without limitation, the following:

              (a) Upon delivery of written instructions from Principal, Agent
shall immediately cause the Massery Interest and any interest related thereto to
be transferred and assigned to Principal or to such other person, persons or
entities as Principal may, in Principal's sole discretion, designate.

              (b) Any and all notices, statements and communications received by
Agent as owner or with respect to the Massery Interest shall be promptly given
to Principal.

              (c) If Agent shall receive any funds and/or any contracts and
documents executed in connection or accordance herewith with respect to the
Massery Interest or the Property, Agent shall disburse such funds in accordance
with the directions of Principal, either directly to Principal or to such
persons, firms and/or entities as Principal may, in Principal's sole discretion,
designate. Agent shall account to Principal for all funds so received by Agent
on behalf of Principal in such reasonable manner as Principal may from time to
time require.

              (d) If Principal desires to use the Property in a "like-kind"
exchange transaction pursuant to section 1031 of the Code, Agent shall cooperate
with and assist Principal in all reasonable respects in order to insure that the
exchange so qualifies as a "like-kind" exchange under section 1031 of the Code
and the Treasury Regulations promulgated, or to be promulgated, thereunder,
provided that such cooperation and assistance does not require Agent to take any
action which would, in Agent's opinion, involve Agent in any liability unless
Agent shall have first been indemnified to its satisfaction.


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      3. Without the express written consent of Principal, Agent hereby
covenants not to disclose this Agreement or any of the terms, conditions or
other facts contained herein (other than the professionals involved in the
transaction herein contemplated or any party otherwise involved in the
respective businesses of either party hereto), or to issue any press release or
public statement related to the transaction contemplated by this Agreement,
unless required to do so by applicable law or court order, PROVIDED, HOWEVER, if
Principal issues any such press release or public statement other than one which
Principal is required to issue or make by court order or applicable law
(including all rules and regulations of the Securities Exchange Commission or
any public stock or securities exchange), then Agent shall be allowed to issue a
similar press release or public statement which shall be limited to such facts
and information as are set forth in Principal's press release or public
statement.

      4. The authority and duties of Agent hereunder shall not be delegated or
assigned by Agent except at the written direction or with the prior written
consent of Principal.

      5. Insofar as third persons dealing with Agent are concerned, Agent is
only to act as the agent and nominee of Principal and, as such, the following
provisions shall govern:

              (a) Agent, solely in its capacity as agent and nominee for
Principal (and solely with respect to third parties unless done pursuant to
Principal's written instructions or request) shall have full right, power and
authority to deal with the Massery Interest held by Agent hereunder, with the
same force and effect as though such Massery Interest were individually owned by
it; and, without limiting the generality of the foregoing; including full right
to execute and deliver any assignment or transfer relating to the Massery
Interest or any other any other instrument relating thereto.

              (b) Any and all of the foregoing instruments executed by Agent may
create obligations extending over periods of time, including periods extending
beyond the date of any possible termination of this Agreement;

              (c) No third party dealing with Agent shall be under any
obligation to inquire as to the propriety of any action or omission by Agent,
and such third party shall be conclusively protected in assuming without further
inquiry that any action taken by Agent, or any officer or employee of it acting
individually, including the execution of any instrument, is a valid and duly
authorized act of Agent as nominee and agent of Principal; and

              (d) Any member of Agent shall have full authority to execute any
and all instruments or take any and all other action which Agent is authorized
and empowered so to do by the terms of this Agreement.

      6. As between Agent on the one hand, and Principal on the other, it is
understood and agreed that Principal shall have full and exclusive power to
manage, own and deal with the Massery Interest including, without limitation,
supervising, directing and controlling any litigation, or the sale of the
Massery Interest or otherwise, assigning, conveying or disposing of the Massery
Interest. It is further understood and agreed that Agent shall act solely as the
agent


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and nominee of Principal with respect to the Massery Interest and as such, when,
as, if and to the extent specifically directed by Principal shall :

              (a) Execute any instruments, including without limitation,
governmental filings, as Agent may from time to time be specifically directed by
Principal in writing;

              (b) Take any such action with respect to the Massery Interest as
may from time to time be specifically directed by Principal in writing;

              (c) Do any such other things as Agent may be specifically directed
to do by the terms of this Agreement; EXCEPT THAT Agent shall not be required to
take any action which would, in the opinion of Agent, involve Agent in any
liability unless Agent shall have first been indemnified to its satisfaction;
and

              (d) Execute only such instruments and take only such action as
shall have been authorized and directed by Principal in writing.

The provisions of this Paragraph 6 shall be applicable only as between Agent on
the one hand, and Principal on the other; but the limitations set forth in this
Paragraph 6 shall in no way limit the rights of third parties against the
Principal, or with respect to the Property for any actions taken by the Agent
pursuant to Paragraph 5 above.

      7. This Agreement shall be terminated at any time by Principal, by notice
in writing to Agent, signed and fully acknowledged, or, in all events, upon
conveyance by Agent of the Massery Interest or the Property to Principal or
Principal's designee. If the Massery Interest has not been transferred and
conveyed to Principal at the time of termination of this Agreement, Agent shall
transfer and convey title to the Massery Interest (or the Property) to Principal
at such time.

      8. This Agreement may be amended from time to time by an instrument in
writing, signed by all parties.

      9. Agent shall not be liable for any error of judgment, nor for any loss
arising out of any act or omission in good faith, but shall be responsible only
for its own willful breach of the provisions hereof. Principal shall be liable
for all debt and liabilities arising out of or occurring in connection with the
Massery Interest to the same extent and subject to the same limitations,
contractual or otherwise, as if the Principal were the record owner of the
Massery Interest

      10. In the construction hereof, whether or not so expressed, words used in
the singular or in the plural, respectively, include both the plural and
singular, words denoting males include females and words denoting persons
include individuals, firms, associations, companies, trusts and corporations,
unless a contrary intention is to be inferred from or required by the subject
matter or context.

      11. This Agreement may not be assigned by Agent or Principal; PROVIDED,
HOWEVER, that Principal may assign this Agreement to any directly or indirectly
wholly-owned subsidiary


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or subsidiaries of Principal, any "qualified intermediary" (as such term is
defined in Treasury Regulation section 1.1031(k)-1(g)(iii)), any "exchange
accommodation titleholder" (as such term is defined in Revenue Procedure
2000-37, 2000-40-IRB) or any other accommodation or other party in connection
with facilitating a "like-kind" exchange under section 1031 of the Code (any
such permitted assignees, a "PERMITTED ASSIGNEE"). Any other assignment or
attempted assignment of this Agreement by Principal or Seller shall constitute a
default by such party hereunder and shall be deemed null and void and of no
force and effect.

      12. All the trusts, powers and provisions herein contained shall take
effect and be construed in accordance with the laws of the State of New York,
without regard to conflicts of laws principles.

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                                                                  EXECUTION COPY


      WITNESS the execution hereof, under seal, in any number of counterpart
copies, each of which counterpart copy shall be deemed an original for all
purposes, as of the day first written above.

                                 ROBERT MARTIN COMPANY, LLC, a New York limited
                                 liability company


                                 By: /s/ Robert F. Weinberg
                                     --------------------------
                                 Name:    Robert F. Weinberg
                                 Title:   Manager


                                 5/6 SKYLINE REALTY L.L.C., a New York limited
                                 liability company

                                 By:   Mack-Cali Realty, L.P., a Delaware
                                       limited partnership, its sole member

                                       By:  Mack-Cali Realty Corporation,
                                            a Delaware corporation, its
                                            general partner


                                       By:  /s/  Roger W. Thomas
                                            -----------------------
                                            Roger W. Thomas,
                                            Executive Vice President