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                                                                   Exhibit 10.52

                          ELEVENTH AMENDMENT TO LEASE

      This Amendment made as of the 7th day of February, 1997 is by and between
Grove Street Associates of Jersey City Limited Partnership, a New Jersey limited
partnership having an office at c/o Cali Realty Corporation, 11 Commerce Drive,
Cranford, New Jersey 07016 (hereinafter called "Landlord"), and Donaldson,
Lufkin & Jenrette Securities Corporation, a Delaware corporation having an
office at 277 Park Avenue, New York, New York 10172 (hereinafter called
"Tenant").

                                   WITNESSETH

      WHEREAS, Landlord and Tenant have previously entered into a Lease as
described on the attached Schedule #1 covering certain premises in the building
at 1 Pershing Plaza, Jersey City, New Jersey (the "Building"); and

      WHEREAS, Tenant wishes to use a portion of the space on the top floor of
the Building's parking garage for the installation of dry coolers.

      WHEREAS, Landlord and Tenant desire to amend the Lease as set forth
herein.

      NOW, THEREFORE, in consideration of the foregoing, the sum of Ten Dollars
($10.00) and other good and valuable consideration the receipt and sufficiency
of which are hereby acknowledged, Landlord and Tenant do hereby agree to amend
and modify the Lease as follows:

1.    All defined terms used in this Amendment shall have the meanings ascribed
      to them in the Lease unless otherwise defined herein.

2.    The recitals set forth above are incorporated herein by reference.

3.    Subject to the terms of this Agreement, Landlord hereby grants Tenant the
      right to install dry coolers and associated screening applicable thereto
      (the "Installation") on the roof of the parking garage of the Building.

4.    The Installation shall:

      a)    be located on the top floor of the parking garage adjacent to the
            Building as shown cross-hatched on Exhibit A attached hereto;

      b)    be governed by the provisions of Article 13 "Tenants" Changes of the
            Lease without regard to the cost of the Installation except that
            Article 13.01(b) of the Lease shall be waived as it applies to the
            installation.

      (c)   include a metal louvered screening system around the dry coolers no
            less than 5' 6" in height.

      (d)   provide door access to it only from the south side of same.

      (e)   at Landlord's option, shall be removed by Tenant at Tenant's expense
            upon the Expiration Date or sooner termination of the Lease and
            Tenant shall fully repair any damage to the Building and parking
            garage resulting from such removal (this obligation shall survive
            the expiration or termination of the Lease).

5.    Upon completion of the Installation, the number of Free Spaces as defined
      in Article 45.03 shall be reduced to thirty-seven (37) from fifty (50).
      The parties hereto acknowledge ten (10) Free Spaces have been previously
      deducted from the original total when Tenant elected to use same for the
      installation of the sixth floor cooling towers, the fifth floor sump tanks
      and the ground floor fuel oil storage tank. In the event the Installation
      is removed by Tenant prior to the Expiration Date or sooner termination of
      the Lease, the Free Spaces shall be increased to forty (40) from
      thirty-seven (37).


                                       1
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6.    Tenant represents and warrants that this Lease and the undersigned's
      execution of same has been duly authorized and approved by the
      corporation's Board of Directors. The undersigned officer of the
      corporation represents and warrants he is an officer of the corporation
      with authority to execute this Lease on behalf of the corporation.
      Landlord represents and warrants that this Amendment and the undersigned's
      execution of same has been duly authorized and approved by all necessary
      partnership and corporate actions. The undersigned officer of the
      corporate general partner of Landlord represents and warrants that he is
      an officer of the corporation with authority to execute this Amendment on
      behalf of the corporate general partner of Landlord, and that the
      corporate general partner of Landlord is authorized to execute this
      Amendment on behalf of Landlord.

      EXCEPT as modified herein, the Lease dated July 1, 1987 and all amendments
and sideletters applicable thereto covering the Premises shall remain in full
force and effect as if the same had been set forth in full herein and Tenant and
Landlord hereby ratify and confirm all of the terms and conditions thereof.
Tenant acknowledges that it has no offsets, defenses or counterclaims to its
obligations under the Lease as amended hereby.

      THIS Amendment shall be binding upon and inure to the benefit of the
parties hereto and their respective legal representatives, successors and
permitted assigns.

GROVE STREET ASSOCIATES OF                DONALDSON, LUFKIN & JENRETTE
JERSEY CITY LIMITED PARTNERSHIP,          SECURITIES CORPORATION,
(Landlord)                                (Tenant)

By:   Cali Sub IV, Inc.
      General Managing Partner

By:   /s/ James G. Nugent                 By:   /s/ Robert A. Yurman
      ----------------------------              --------------------------------
      James G. Nugent                           Robert A. Yurman, Vice President
      Vice President - Leasing                  Director of Administration


                                       2
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                     SCHEDULE #1 TO LEASE DATED JULY 1, 1987

LANDLORD: Grove Street Associates of Jersey City Limited Partnership

TENANT: Donaldson, Lufkin & Jenrette Securities Corporation

                            DESCRIPTION OF THE LEASE

DATE OF DOCUMENT                       DOCUMENT
----------------                       --------

July 1, 1987                           Lease
July 1, 1987                           First Amendment of the Lease
July 1, 1987                           Side Letter Amendment
June 19, 1989                          Side Letter Agreement
March 12, 1992                         Second Amendment to Lease
December 27, 1992                      Third Amendment to Lease
September 29, 1993                     Side Letter Agreement
December 23, 1993                      Fourth Amendment to Lease
May 1, 1994                            Fifth Amendment to Lease
March 9, 1995                          Sixth Amendment to Lease
June 16, 1995                          Seventh Amendment to Lease
April 4, 1996                          Eighth Amendment to Lease
April 4, 1996                          Ninth Amendment to Lease
December 31, 1996                      Tenth Amendment to Lease

                                                END

<PAGE>

                    SCHEDULE #2 to Lease dated July 1, 1987

      Landlord: Grove Street Associates of Jersey City Limited Partnership

          Tenant: Donaldson, Lufkin & Jenrette Securities Corporation

                       Description of the LEASED PREMISES

                                        OFFICE          STORAGE       TEMPORARY
       FLOOR(S)                         SPACE            SPACE          SPACE
       --------                         -----            -----          -----

         2-9                           256,925
         10                             35,820
                                       -------
        2-10                           292,745
        Lobby                            4,800
                                       -------
Lobby, 2-10                            297,545
         11                             36,600
                                       -------
Lobby, 2-11                            334,145
Storage(kitchen)                                          8,194
Storage Space #1                                          1,800
Storage Space #2                                          3,747
Temporary Space-12th Floor                                              4,809
Storage-Temporary #1                                                      794
Storage-Temporary #2                                                      112
        14&15                           73,200
                                       -------
Subtotal                               407,345
         12A                             6,507                0             0
                                       -------           ------         -----
TOTAL S.F. AREAS                       413,852           13,741         5,715
                                       =======           ======         =====

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                                    EXHIBIT A

                              [FLOOR PLAN OMITTED]