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                                                                 EXHIBIT 10.40

                                   PROMISSORY NOTE


$2,000,000.00                                                  Vienna, Virginia
Maturity Date: July 12, 2006                                  July 12, 1996

     FOR VALUE RECEIVED, the undersigned, NHP INCORPORATED, a Delaware
corporation ("Maker"), hereby promises to pay to the order of DIANA L. GOLDBERG
or any subsequent holder or holders ("Holder") of this Promissory Note (this
"Note"), at 4400 Garfield Street, N.W., Washington, D.C.  20007, or at such
other place as Holder may from time to time designate in writing, the principal
sum of Two Million Dollars ($2,000,000.00), together with all accrued interest
on such outstanding balance, in accordance with the terms and provisions of this
Note.

     1.      INTEREST; PAYMENTS.  Interest shall accrue on the unpaid principal
balance of this Note from and after the date of this Note at the rate of nine
and one-half percent (9 1/2%) PER ANNUM, compounded quarterly, and payments of
interest only shall be made quarterly, commencing on the first (1st) day of
October, 1996 in the amount of Forty-One Thousand Three Hundred Four Dollars and
Thirty-Five Cents ($41,304.35), and continuing thereafter on the first (1st) day
of each of January, April, July and October, in the amount of Forty-Seven
Thousand Five Hundred Dollars and No Cents ($47,500.00), until April 1, 2006,
inclusive.

      2.      MATURITY.  The entire unpaid principal balance of this Note,
together with all accrued but unpaid interest thereon, shall be due and payable
in full on the tenth (10th) anniversary of the Closing, as defined in that
certain Purchase Agreement by and among, among others, Holder and Maker dated as
of June 28, 1996 (the "Maturity Date").

     3.      PREPAYMENT.  Maker shall have the right to prepay, in part or in
full, without penalty, this Note at any time or times.

     4.      EXTENSION.  From time to time, without in any way affecting the
obligation of Maker to pay the outstanding principal balance of this Note and
any interest accrued thereon and fully to observe and perform the covenants and
obligations of Maker under this Note, without giving notice to, or obtaining the
consent of, Maker, and without any liability whatsoever on the part of Holder,
Holder may, at its option, extend the time for payment of interest hereon and/or
principal of this Note, reduce the payments hereunder, release anyone liable on
this Note or accept a renewal of this Note, join in any extension or
subordination, or exercise any right or election hereunder.  No one or more of
such actions shall constitute a novation or

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operate to release any party liable for or under this Note, either as Maker or
otherwise.

     5.      EVENTS OF DEFAULT.  Maker's failure to make any required payment of
principal and/or interest under this Note on or before the date such payment is
due, and Maker's failure to make such payment within fifteen (15) days after
Maker's receipt of written notice from Holder of such failure shall be an "Event
of Default" hereunder.

     6.      REMEDIES.  Upon the occurrence of an Event of Default, Holder shall
have the right to cause the entire unpaid principal balance, together with all
accrued and unpaid interest thereon, reasonable attorneys' fees and all fees,
charges, costs and expenses, if any, owed by Maker to Holder hereof, to become
immediately due and payable in full by giving written notice to Maker.  Upon the
occurrence of an Event of Default, Holder may avail itself of any and all legal
and equitable rights and remedies which Holder may have at law or in equity or
under this Note, including, but not limited to, the right to accelerate the
indebtedness due under this Note as described in the preceding sentence.  The
remedies of Holder hereof as provided herein shall be distinct and cumulative,
and may be pursued singly, successively, or together, at the sole discretion of
Holder, and may be exercised as often as occasion therefor shall arise.  Failure
to exercise any of the foregoing options upon the occurrence of an Event of
Default shall not constitute a waiver of the right to exercise the same or any
other option at any subsequent time in respect of the same or any other Event of
Default, and no single or partial exercise of any right or remedy shall preclude
other or further exercise of the same or any other right or remedy.  Holder
shall have no duty to exercise any or all of the rights and remedies herein
provided or contemplated.  The acceptance by Holder of any payment hereunder
that is less than payment in full of all amounts due and payable at the time of
such payment shall not constitute a waiver of the right to exercise any of the
foregoing rights or remedies at that time, or nullify any prior exercise of any
such rights or remedies without the express written consent of Holder.

     7.      GOVERNING LAW.  The provisions of this Note shall be governed and
construed according to the law of the Commonwealth of Virginia, without giving
effect to its conflicts of laws or choice of laws provisions.

     8.      NOTICES.

(a)      All notices hereunder shall be in writing and shall either be hand
delivered, with receipt therefor, or sent by Federal Express or similar courier,
with receipt therefor, or by

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certified or registered mail, postage prepaid, return receipt requested, as
follows:

If to Maker:     NHP INCORPORATED
                 1225 Eye Street, N.W.
                 Washington, D.C.  20005
                 Attn:  Senior Executive of Asset Management
                        Senior Executive of Acquisitions
                        General Counsel
                        Secretary

With copy to:    TUCKER, FLYER & LEWIS
                 1615 L Street, N.W., Suite 400
                 Washington, D.C.  20036
                 Attn:  Thomas J. Knox, Esq.

If to Holder:    Diana L. Goldberg
                 4400 Garfield Street, N.W.
                 Washington, D.C.  20007

Notices shall be effective when received.

             (b)      Any of the foregoing persons may change the address to
which notices are to be delivered to it hereunder by giving written notice to
the others as provided in this Paragraph 8.

     9.      SEVERABILITY.  In the event that any one or more of the provisions
of this Note shall for any reason be held to be invalid, illegal or
unenforceable in any respect, such invalidity, illegality or unenforceability
shall not affect any other provision of this Note, and this Note shall be
construed as if such invalid, illegal or unenforceable provision had never been
contained herein.

     10.      LIMITATIONS OF APPLICABLE LAW.  In the event the operation of any
provision of this Note results in an effective rate of interest transcending the
limit of the usury or any other law applicable to the loan evidenced hereby, all
sums in excess of those lawfully collectible as interest for the period in
question shall, without further agreement or notice by any party to this Note,
be applied to the unpaid principal balance of this Note immediately upon receipt
of such monies by Holder, with the same force and effect as though Maker had
specifically designated such extra sums to be so applied to the unpaid principal
balance and Holder had agreed to accept such extra payment(s) as a prepayment.

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     11.      CAPTIONS.  The captions herein are for convenience of reference
only and in no way define or limit the scope or content of this Note or in any
way affect its provisions.

     12.      DEBTOR-CREDITOR RELATIONSHIP.  Holder shall in no event be
construed for any purpose to be a partner, joint venturer or associate of Maker,
it being the sole intention of the parties to establish a relationship of debtor
and creditor.

     13.      TIME OF THE ESSENCE.  It is expressly agreed that time is of the
essence in the performance of the obligations set forth in this Note.


     IN WITNESS WHEREOF, Maker has executed this Promissory Note on this 12th
day of July, 1996, pursuant to due authority.

<TABLE>
<CAPTION>
                              MAKER:

                              NHP INCORPORATED,
                                a Delaware corporation


                              <S>  <C>
                              By:
                                   ---------------------------
                                   Linda Davenport, Executive
                                   Vice President
</TABLE>

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