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                                                                   Exhibit 10.52




                            Translation from Russian



                             LAND SUBLEASE AGREEMENT


                                     BETWEEN

                       OAO "PIONEER FIRST INVESTMENT FUND"

                                       AND

                       PIONEER REAL ESTATE ADVISORS, INC.











                                  MOSCOW, 2000





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                             LAND SUBLEASE AGREEMENT


City of Moscow                                                    April 18, 2000


Open joint-stock company "Pioneer First Investment Fund", a legal entity under
the laws of the Russian Federation (hereinafter - "the Lessee"), represented by
ZAO "'Pioneer First' Company for Management of Investment Funds", in the person
of General Director Maria N. Churayeva, acting on the basis of the Charter of
ZAO "'Pioneer First" Company for Management of Investment Funds" and the power
of attorney of October 05, 1999 issued by OAO "Pioneer First Investment Fund",
on the one hand, and

"Pioneer Real Estate Advisors, Inc.", a legal entity under legislation of the
State of Delaware, USA (hereinafter - "the Sublessee"), in the person of Gren
Carr-Jones, acting on the basis of the power of attorney of December 14, 1999,
on the other hand,

hereinafter jointly referred to as "the Parties",

WHEREAS the Lessee, acting on the ground of Land Lease Agreement in the City of
Moscow No. M-09-000979 of September 6, 1994, has the right of long-term
leasehold of the land site ("the Site") with an area of 12 696 sq. m located at:
24 Smolnaya St., Moscow, Russian Federation;

WHEREAS the Lessee is the owner of a 19-floor administrative and office building
situated on the Site, which was leased on a long term basis to the Sublessee
under the Master Lease Agreement of July 1, 1996;

WHEREAS the Parties intend to legalize the Sublessee's right of leasehold of the
Site in the established order by entering into a sublease agreement; and

WHEREAS, in accordance with the Law of the City of Moscow No. 34 of July 16,
1997 "On the Bases of Chargeable Land Use in the City of Moscow" the Lessee has
made the payment for the right to conduct transactions with the lease rights in
the full amount (the right of lease is purchased) and in accordance with part 2
of Article 615 of the Civil Code of the Russian Federation and clause 3 of
Regulations for subleasing land plots in the City of Moscow approved by
Instruction No. 1129-rm of November 9, 1998 of the Mayor of Moscow, the right to
subleasing the Site to third parties is obtained,



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have concluded this Agreement as follows:

1.     DEFINITIONS USED IN THIS AGREEMENT AND THEIR INTERPRETATION

1.1.   Definitions

For the sake of use in this Agreement, the terms specified in the Lease
Agreement shall have the same meaning when used in this Agreement. The terms
given below shall have the following meaning (if the context and content of this
Agreement do not require otherwise):

LESSOR means Administration (Mayor's Office) of the City of Moscow represented
by the Moscow Land Committee;

RENT means the sums paid by the Lessee to the Lessor for use of the Site in
accordance with the Lease Agreement (land payments);

LEASE AGREEMENT means lease of a land site (Agreement on Lease of Land in the
City of Moscow) No. M-09-000979 concluded between the Lessor and the Lessee on
September 06, 1994, including all subsequent amendments and annexes thereto,
under which the Lessee has the right of long-term leaseholding of the Site;

CHANGE OF RENT means change of the amount of Rent after the signing by the
Parties of this Agreement made as a result of amendments and/or additions to the
Lease Agreement, in case of centralized changes (introduction, alteration and/or
annulment) of rent rates and/or indexes to rent rates owing to the adoption of
normative acts of the RF and/or the City of Moscow, Rent indexation in case of
adoption of a respective normative act of the City of Moscow, and also as a
result of introduction, according to normative acts of the RF and/or the City of
Moscow, of any tax or other obligatory payments to the budget (except for VAT)
added to Rent and payable by the Lessee under the Lease Agreement;

CHANGES OF PROCEDURE OF RENT PAYMENT means full or partial change of the
procedure of paying Rent made after the signing by the Parties of this Agreement
(including changes of the forms of settlement, regularity and/or time of making
land payments, establishment of advance payments) following the amendments
and/or additions to the Lease Agreement, and also in the case of centralized
change of the procedure of paying Rent in Moscow according to normative acts of
the City of Moscow and/or the RF;

CHANGED RENT means the amount of Rent established following the respective Rent
Change;


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COMMUNICATIONS means sewer pipes, ditches, pipelines and conduits, cables,
gutters and any other facilities to channel and transmit sewage, water, gas,
electricity, air, smoke, light, information and other signals, substances and
materials, including, if need be, auxiliary equipment and facilities;

DEFAULT means failure to perform or undue performance by any of the Parties of
its obligations under this Agreement and also of obligations imposed by the
legislation of the RF and/or normative acts of the City of Moscow with respect
to relations of the Parties under this Agreement;

DEFAULTING PARTY means a Party which has defaulted and/or permitted Default;

PLAN means the plan and description of the Site attached as Annex No. 1 hereto;

SUBLEASE PAYMENT means sums paid by the Sublessee to the Lessee for use of the
Site under this Agreement;

PERMITTED USE means objectives of using the Site as provided for by the Lease
Agreement. Permitted Use shall mean use of the Site for location, servicing and
disposal of the multi-floor administrative and office building and creation of a
business center therein, including placement of engineering facilities,
auxiliary and maintenance services required to ensure operation of the business
center, as well as of an open parking lot to be used for cars of lessees and
visitors of the center;

RF means the Russian Federation.

1.2.   Interpretation

       With respect to this Agreement and the Annexes hereto in all cases (if
       not otherwise provided by this Agreement):

1.2.1. references to a document shall mean references to any valid documents
       (including this Agreement), as well as any written statements,
       notifications and other documents; references to documents or any
       provisions thereof shall also mean references to the documents with all
       amendments and additions thereto, as well as revivals and replacement of
       the documents approved by the Parties (in full or in part);


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1.2.2. references to laws and normative acts shall mean references to laws and
       normative acts with all amendments and additions thereto, and also
       newly-adopted laws and normative acts replacing laws and normative acts
       previously in force;

1.2.3. references to any definite Article, clause or Annex shall mean references
       to the definite Article, clause or Annex herein.

1.3.   Headings

       Headings in the text of this Agreement are given solely for ease of
       reference, and should not affect the interpretation of the provisions
       hereof.

2.     SUBJECT OF THE AGREEMENT

2.1    Upon the Lessor's consent the Lessee hereby subleases to the Sublessee
       and Sublessee subleases from the Lessee the Site for a long term use.

       The Sublessee shall pay to the Lessee Sublease Payment for using the
       Site.

2.2.   Cadastral number of the Site - 77-09-01010010.

       Landscape (quality) parameters of the Site:

       -      total area of the Site - 12 696 (twelve thousand six hundred
              ninety six ) square meters;

       -      relief of the Site terrain is even.

       Situated on the Site are:

       -      19-floor administrative and office building known as the
              "Commercial Center Meridian" including basement and mechanical
              equipment room;

       -      main gas pipeline;

       -      heating pipeline system;

       -      out-door parking lot;

       -      green plantations.

2.3.   The boundaries of the Site are fixed with special signs and indicated on
       the Plan.

2.4.   The Site shall be leased to the Sublessee for Permitted Use.
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2.5.   The Site shall be transferred by the Lessee to the Sublessee by an act of
       transfer and acceptance in condition compliant with the requirements of
       the effective legislation of the RF and the normative acts of the City of
       Moscow.

3.     TERM

3.1.   The Agreement shall remain in force until September 06, 2043, i.e. within
       the remaining term of the Lease Agreement.

3.2.   The Agreement shall come into effect from the date of its state
       registration.

3.3.   If the Lessee exercises its pre-emptive right to extend the Lease
       Agreement in accordance with the Article 4.1 of the Lease Agreement, the
       Sublessee shall acquire an analogous right to extend the term of this
       Agreement on conditions agreed by the Parties. To exercise the above
       mentioned right to extend the term of this Agreement the Sublessee shall
       send to the Lessor a written notice not later than 60 (sixty) calendar
       days before the expiration of the term of the Agreement stipulated in
       this clause.

4.     SUBLEASE PAYMENT

4.1.   Sublease Payment shall be made by the Sublessee by way of transfer of the
       due sum to the bank account of the Lessee. The amount of Sublease Payment
       due for any period of time shall be equal to the amount of Rent for a
       corresponding period increased by 10%.
       Should the Site be used in violation of the established town-planning
       priorities or land use regulations (violation of Permitted Use),
       increased coefficients shall also be applied to the Rent rate used to
       calculate Sublease Payment pursuant to the provisions of the Lease
       Agreement and Annex No. 5 to Order No. 980-RM of the Moscow Mayor of
       25.09.1998.

4.2.   Sublease Payment calculated in accordance with clause 4.1 herein shall
       not include VAT due with respect to the Sublease Payment as provided by
       legislation of the RF. Sublease Payment paid by the Sublessee shall be
       increased by the amount of VAT calculated at the rate provided for by
       legislation of the RF. Should new types of taxes analogous to VAT due
       with respect to the Sublease Payment in addition to or in lieu of VAT be
       introduced by legislation of the RF and/or the City of Moscow after
       signing of this Agreement by the Parties, then Sublease Payment payable
       by the Sublessee will have to be increased by the size of the respective
       tax.


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4.3.   As of the date of coming of this Agreement into effect, the annual Rent
       shall be 385 023 rubles 97 kopecks.
       Annual Sublease Payment as of the date of coming of this Agreement into
       effect is equal to 423 526 rubles 37 kopecks (four hundred twenty three
       thousand five hundred twenty six rubles 37 kopecks).

4.4.   In case of Rent Change, the size of Sublease Payment shall be calculated
       in accordance with clause 4.1 hereof where Sublease Payment is equal to
       Changed Rent starting from the date on which the Changed Rent is payable
       by the Lessee in accordance with provisions of the Lease Agreement.

       In case of Change of Rent, the Sublessee shall pay Sublease Payment
       recalculated taking into consideration the amount of Changed Rent upon a
       written notification forwarded by the Lessee to the Sublessee in
       accordance with clause 5.1 hereof.

4.5.   Sublease Payment shall be paid by the Sublessee to the Lessee with
       regularity similar to that provided for by the Lease Agreement for paying
       Rent provided that Sublease Payment must be paid by the Sublessee 15
       (fifteen) calendar days prior the term specified for paying Rent by the
       Lessee for a corresponding period.

4.6.   The procedure of paying Rent as of the date of coming of this Agreement
       into effect is as follows: the annual amount of Rent shall be paid
       quarterly in equal installments not later than on the 5th (fifth) day of
       the first month of a calendar quarter. Manner of payment is bank
       transfer.

       As of the date of coming of this Agreement into force effect, in
       accordance with clause 4.5 hereof the Sublessee must pay the annual
       amount of Sublease Payment quarterly in equal installments not later than
       on the 21 (twenty first) day of the last month of a calendar quarter
       preceding the calendar quarter on account of which the payment is made by
       transfer of corresponding money amounts to the bank account of the
       Lessee.

       The first payment on account of the Sublease Payment shall be made by the
       Sublessee not later than 15 (fifteen) days after the coming of this
       Agreement into effect. The amount of the first payment on account of the
       Sublease Payment is to be determined proceeding from one forth of the
       amount of the Annual Sublease Payment provided by clause 4.3 hereof and
       is calculated pro rata to the number of calendar days remaining


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       towards the end of the current calendar quarter after the date of coming
       of this Agreement into effect.

4.7.   Bank Details of the Lessee:
       INN          7704038268
       Settlement account  40701810600700100065
       with         CB "Citibank T/O"
       Correspondent account        30101810300000000202
       BIK          044525202.
       The Lessee shall be obliged to promptly inform the Sublessee in writing
       about any changes of the above bank account.

4.8.   In case of any Change of the Procedure of Paying Rent, the procedure of
       making Sublease Payment shall also be changed accordingly to ensure
       performance of the requirements of clause 4.5 hereof. The respective
       change of the procedure of making Sublease Payment shall be executed by
       sending by the Lessee to the Sublessee of a written notice in accordance
       with clause 5.1 hereof and shall be applied to the relations between the
       Parties from the day on which Change of the Procedure of Paying Rent
       becomes binding on the Lessee in accordance with the terms of the Lease
       Agreement.

4.9.   The date of making of all payments under this Agreement shall be the day
       on which respective amounts are credited to the correspondent account of
       the bank of the transferee.

5.     RIGHTS AND OBLIGATIONS OF THE LESSEE

5.1.   In case of Change of Rent and/or Change of the Procedure of Rent Payment,
       the Lessee shall have the right to unilaterally change the size of
       Sublease Payment and/or the procedure (timing, terms) of making Sublease
       Payments provided for by this Agreement, by sending to the Sublessee a
       written notification about the changed size of Sublease Payment and/or
       the procedure of making Sublease Payment on the basis of, respectively,
       clauses 4.4 and 4.9 hereof, attaching copies of the documents to confirm
       the fact of the Rent Change and/or the Change of the Procedure of Rent
       Payment. The Parties agree that no amendments to this Agreement are
       necessary if the Lessee complies with the above order of notifying the
       Sublessee about the Rent Change and/or the Change of the Procedure of
       Rent Payment, which changes entail alteration of the size of Sublease
       Payment and/or the procedure of making Sublease Payment.


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5.2.   The Lessee shall comply with all the obligations imposed to him in
       accordance with the Lease Agreement, with due regard to the provisions
       hereof.

5.3.   The Lessee shall not to exercise without preliminary consent of the
       Sublessee the Lessee's right to terminate the Lease Agreement before time
       by sending to the Lessor a respective written notice provided by Article
       4.1 of the Lease Agreement. In case of breach of this obligation the
       Lessee shall compensate the Sublessee for all the losses caused by the
       early termination of the Lease Agreement.

5.4.   The Lessee shall undertake not to interfere with business activity of the
       Sublessee and not to prevent the Sublessee from using the Site in
       accordance with Permitted Use.

5.5.   The Lessee shall undertake to render assistance to the Sublessee in
       obtaining all the licences, approvals and permits which the Sublessee may
       require for Permitted Use of the Site under this Agreement.

5.6.   The Lessee shall guarantee to the Sublessee, workers, employees and
       representatives of the Sublessee, as well as to persons maintaining
       business and other relations with the Sublessee a free and unobstructed
       access to the Site at any time.

5.7.   The Lessee shall undertake to render assistance to the Sublessee in
       upholding the latter's rights of Permitted Use of the Site in accordance
       with the legislation of the RF and the normative acts of the City of
       Moscow.

5.8.   Upon a prior, not later than 10 (ten) days, notice (except in cases of
       emergency) the Lessee and its authorized persons shall have the right to
       enter the Site at any time with the aim of:

5.8.1. laying, inspecting, repairing, replacing, cleaning, maintaining in good
       order of, and joining to, any lines of Communications under the authority
       of the Lessee;

5.8.2. inspecting, cleaning, restoring, developing and maintaining in good
       order, renovating or restructuring the territory adjacent to the Site;

5.8.3. fulfilling the Lessee's obligations under this Agreement or any other
       obligations.


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6.     RIGHTS AND OBLIGATIONS OF THE SUBLESSEE

6.1.   The Sublessee shall have the right to use the Site in accordance with the
       Permitted Use and also for conducting works to develop and improve the
       ecological condition of the Site. The Sublessee and its workers,
       employees and representatives, as well as persons maintaining business
       and other relations with the Sublessee shall have the right of a free and
       unobstructed access to the Site at any time.

6.2.   The Sublessee shall be entitled, in accordance with Permitted Use, to
       place on the Site engineering facilities, objects of auxiliary and other
       services ensuring operation of the business center, as well as an
       out-door parking lot, provided that the Sublessee has obtained in due
       order all permits, licences and approvals from authorized governmental
       and/or municipal bodies required for the construction and mounting of the
       said objects.

6.3.   The Sublessee shall make Sublease Payments in due time as provided for by
       this Agreement.

6.4.   The Sublessee shall use the Site solely for the purposes of Permitted Use
       specified hereby and also for conducting works to develop and improve the
       ecological condition of the Site.

6.5.   The Sublessee shall prevent any actions which can deteriorate quality
       characteristics of the Site and the ecological situation therein and
       cause pollution of the adjacent territory.

6.6.   The Sublessee shall pay on its own all the taxes, duties, fees and other
       charges due in respect of the Sublessee's rights to real estate located
       on the Site as provided by the legislation of the RF and the normative
       acts of the City of Moscow.

6.7.   On the expiry of the sublease term established under this Agreement, the
       Sublessee shall transfer the Site to the Lessee in the condition the Site
       was transferred to the Lessee in accordance with this Agreement, taking
       into account, however, the change of the Site quality characteristics
       resulting from its proper usage.

6.8.   The Sublessee shall provide to the Lessee and state bodies in charge of
       control over the use and protection of land a free access to the Site;
       comply with the requirements of respective services in respect of
       utilization of underground and ground lines of Communications,
       structures, roads, passages etc. and not interfere with repair works and
       servicing thereof.


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6.9.   The Sublessee shall not violate the rights of other land users.

7.     REPRESENTATIONS AND GUARANTIES

7.1.   The Lessee hereby represents and guarantees that:

7.1.1. The Lessee has and shall have the right, under the Lease Agreement, of
       long-term use of the Site on conditions of lease and is authorized to
       enter into this Agreement on the terms specified herein.

7.1.2. In accordance with the Lease Agreement the Lessee has the right to
       sublease the entire Site or part of the Site for a term expiring on
       September 06, 2043.

7.1.3. There are no claims of third persons or any other restrictions with
       respect to the right of use of the Site, which can encumber or contradict
       exercise by the Sublessee of its rights hereunder or which can result in
       the annulment of this Agreement or extra charges on the part of the
       Sublessee.

7.1.4. As of the day of signing this Agreement, the Site is not pledged, neither
       is it claimed, nor sequestered, nor encumbered with other rights of any
       third persons.

7.1.5. The Lessee will provide to the Sublessee any support and assistance in
       exercising by the Sublessee of its rights under this Agreement, including
       provision of necessary conditions for the most beneficial use of the Site
       by the Sublessee.

7.1.6. Should there arise the necessity to seize the Site for governmental
       and/or municipal needs under the effective legislation of the RF and/or
       normative acts of the City of Moscow, the Lessee shall take all possible
       actions to make damage suffered by the Sublessee reduced to the minimum.
       In case of seizure of the Site for governmental or municipal needs the
       Sublessee shall have the right to receive from the Lessee a monetary
       compensation for damages caused by such seizure. The amount of the
       compensation to be paid to the Sublessee shall not exceed the amount of
       analogous compensation actually received by the Lessee in connection with
       the seizure of the Site.

7.2.   The Sublessee represents and guarantees that:


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7.2.1. The Sublessee is authorised to enter into this Agreement on the terms
       specified herein.

7.3.   Each of the Parties represents, guarantees and agrees that the conclusion
       of this Agreement will not lead to any breach or non-fulfillment of
       conditions of any contract or agreement by which a Party or any of its
       property is bound, nor of any law, regulation, decree or other legal act
       governing that Party's activity.
7.4.   The Party having breached any of its representations or guarantees
       stipulated herein shall compensate the other Party for all the losses
       suffered as a result of such breach.

8.     LIABILITY OF THE PARTIES

8.1.   In case of Default by one of the Parties, the other Party shall send to
       the Defaulting Party a written notification containing the description of
       the Default, demanding its elimination and specifying the reasonable time
       limits for such elimination.

8.2.   The Defaulting Party must eliminate Default within the time limits
       specified in the notification of Default. If Default cannot be eliminated
       in due time because of its nature, the Defaulting Party shall take all
       possible endeavours in order to eliminate Default within the term to be
       agreed upon by the Parties additionally.

8.3.   Should the Sublessee fail to make Sublease Payment in good time in
       accordance with this Agreement, the Sublessee shall pay to the Lessee a
       penalty at the rate of 0.2 (two tenths) percent of the amount of the debt
       for every day of delay.

8.4.   The Parties shall be held responsible for breach of the terms and
       conditions of the Agreement in accordance with the effective legislation
       of the Russian Federation and/or the normative acts of the City of
       Moscow.

9.     DISPUTE RESOLUTION. APPLICABLE LAW

9.1.   The Parties shall take all reasonable endeavors to resolve all disputes
       arising under this Agreement by way of negotiations.

9.2.   All disputes, differences and claims arising from this Agreement or in
       connection with it shall be resolved in accordance with applicable
       legislation of the Russian Federation.

9.3.   If the Parties are unable to resolve the dispute by mutual negotiation,
       then any dispute, difference or claim arising out of this Agreement or in
       connection with it shall be


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        referred to an arbitration court in accordance with the procedure
        provided by the laws of the Russian Federation.

10.     AMENDMENTS IN THE AGREEMENT

10.1.   Any amendments and additions to this Agreement, except for the cases
        provided by clause 5.1 hereof, shall be valid only if made in writing
        and signed by authorized representatives of the Parties.

10.2.   Amendments and additions to this Agreement shall be subject to state
        registration.

11.     TERMINATION OF THE AGREEMENT

11.1.   The Sublessee shall have the right to terminate this Agreement:

11.1.1. if the Lessee has breached the material terms and conditions hereof;

11.1.2. in case of termination of the Master Lease Agreement of July 1, 1996
        between the Lessee and the Sublessee;

11.1.3. in other cases provided by the legislation of the RF.

11.2.   The Lessee shall have the right to terminate this Agreement:

11.2.1. if the Sublessee has breached the material terms and conditions hereof;

11.2.2. if the Site has been seized for governmental or municipal needs in the
        cases provided for by the RF legislation and/or the normative acts of
        the City of Moscow;

11.2.3. in other cases provided for by the legislation of the RF. Under the
        material breach of this Agreement by the Sublessee shall be understood,
        among other things, the delay of Sublease Payment for more than 12
        (twelve) calendar months.

12.     REGISTRATION OF THE AGREEMENT

12.1.   This Agreement shall be duly signed by duly authorized representatives
        of both Parties and is subject to registration with the Moscow City
        Committee for State Registration of


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       the Rights to Real Estate and Transactions with It in the order provided
       for by the effective RF legislation and/or normative acts of the City of
       Moscow.

13.    CONFIDENTIALITY

13.1.  The Parties shall not disclose the terms and conditions of this Agreement
       and the circumstances of signing hereof (hereinafter - "Confidential
       Information"), and neither Party shall have the right to transfer
       Confidential Information to any third parties (except affiliated
       companies) without written consent of the other Party, provided that any
       of the Parties shall have the right to inform authorized state
       institutions empowered to get such Confidential Information, the Parties'
       legal advisers and auditors, as well as the competent court of
       arbitration in order to confirm any Party's claims or provide legal
       protection against the claim lodged with respect to such a Party in
       connection with this Agreement.

14.    FORCE MAJEURE

14.1.  The Parties shall be relieved of responsibility for any nonfulfillment in
       whole or in part of their obligations if it is caused by force-majeure
       circumstances, including but not limited to war, civil uprising,
       rebellion, civil or military conflict, acts of sabotage, strike, lockout,
       fire, floods or other natural disasters. Notwithstanding the foregoing,
       if as a result of such force-majeure circumstances, one of the Parties is
       unable to fulfill its obligations, that Party shall immediately inform
       the other Party of occurrence of such circumstances and take all measures
       that it deems expedient in order to protect the interests of the other
       Party. The Parties shall not have the right to demand compensation for
       any losses arising as a consequence of such unfulfilled obligations.

15.    NOTICES AND ADDRESSES OF THE PARTIES

15.1.  If otherwise is not expressly specified in this Agreement, any
       notification, authorization or consent forwarded by one Party to the
       other shall be made in writing and can be sent by courier, telegraph or
       fax. In case a notification is sent by fax, it must be, without a delay,
       confirmed by registered mail or messenger mail to the address of the
       recipient Party given below.


<PAGE>   15

15.2.  Addresses of the Parties are as follows:

       15.2.1.    Lessee:
       Bldg. D, 24 Smolnaya St., 145445 Moscow
       Fax: (095) 960 29 05


       15.2.2.    Sublessee:
       60 State Street, Boston,
       MA, USA
       145445, Moscow
       Smolnaya Str., 24 build.D.
       Fax: (095) 960 29 20

       The Parties shall promptly inform each other about changes in their
       addresses and fax numbers.

15.3.  All notifications and messages forwarded by one of the Parties to the
       other Party in connection with this Agreement shall be deemed effective
       upon the receipt thereof.

16.    OTHER CONDITIONS

16.1.  If any of the provisions under this Agreement becomes invalid, this shall
       not result in other provisions hereof being ineffective. Wherever
       necessary, the Parties may agree to replace the invalid provision with an
       effective one meeting to the utmost the purpose of the Agreement and
       making its possible to achieve a similar economic result.

16.2.  The Sublessee shall not be entitled to transfer its rights and
       obligations under this Agreement to any third parties without a
       preliminary written consent of the Lessee and the Lessor. Notwithstanding
       anything in this clause to the contrary, the Lessee hereby grants its
       consent for transfer by the Sublessee of its rights and obligations under
       this Agreement to any entity controlling, controlled by or under the
       common control of Pioneer Real Estate Advisors, Inc.

16.3.  The Sublesse shall not be liable to the Lessee directly or vicariously
       for the acts or omissions of third parties nor any damages caused to the
       Lessee as a result of the acts or omissions of third parties. Except for
       the Sublessee's own acts of willful misconduct or gross negligence, the
       Sublessee shall not be liable for any damages caused to the Lessee for
       actions taken in good faith in connection with performing its obligations
       under this Agreement.


<PAGE>   16
16.4.  Subject to the provisions of clause 16.3 hereof, if either Party breaches
       any of its obligations under this Agreement, such Party shall compensate
       the other party for any actual damages caused by such breach, but shall
       not be liable for any subsequent or consequential damages suffered as a
       result of the breach.

16.5.  Except when caused by the willful misconduct or gross negligence of the
       Sublessee, the Lessee shall indemnify and hold the Sublessee harmless
       from and against all claims, costs, damages, judgements, attorneys' fees,
       expenses, obligations and liabilities of any kind or nature that the
       Sublessee shall incur or sustain in good faith in connection with or
       arising out of its obligations under this Agreement. Notwithstanding the
       foregoing, the Lessee shall not be liable and shall not indemnify the
       Sublessee for any claims, damages or judgements related to any labor
       disputes arising from employment relationship established by the
       Sublessee.

16.4.  All annexes to this Agreement shall be an integral part hereof.

In witness thereof this Agreement is executed and signed on April 18, 2000 in
the City of Moscow in four original copies in the Russian language.


                           SIGNATURES OF THE PARTIES:


OAO "Pioneer First                       Company "Pioneer Real
Investment Fund"                         Estate Advisors, Inc."

/s/ Churayeva M.N.                       /s/ Gren Carr-Jones
-----------------------------            -----------------------------------
Churayeva M.N.                           Gren Carr-Jones
General Director                         by Power of Attorney dated December 14,
                                         1999
of Management Company
ZAO "Pioneer First"
by Power of Attorney dated 05.10.1999


<PAGE>   17


THE PIONEER GROUP, INC.

60 State Street
Boston, MA 02109-1820
617-742-7825

[PIONEER LOGO]

       The undersigned hereby certifies that the translation of the Land
Sublease Agreement dated as of April 18, 2000 by and between Open Joint-Stock
Company "Pioneer First Investment Fund" and Pioneer Real Estate Advisors, Inc.
to which this certification is attached is a fair and accurate translation of
the original document executed in Russian.

Dated: June 9, 2000

                              /s/ Catherine Mannick
                              ----------------------------
                             Name: Catherine Mannick
                             Title:  Vice President and Assistant General
                             Counsel, The Pioneer Group, Inc.