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                                                                   Exhibit 24.8

                              POWER OF ATTORNEY


STATE OF MARYLAND
COUNTY OF MONTGOMERY


     KNOW ALL MEN BY THESE PRESENTS that Henry H. Goldberg, having an address
at 7200 Wisconsin Avenue, Suite 1000, Bethesda, MD 20814, has made,
constituted and appointed and BY THESE PRESENTS, does make, constitute and
appoint Douglas Crocker II and Michael J. McHugh, or either of them, having
an address at Two North Riverside Plaza, Chicago, Illinois 60606, his true
and lawful Attorney-in-Fact for him and his name, place and stead to sign and
execute in any and all capacities this Annual Report on Form 10-K and any or
all amendments to this Annual Report granting unto each of such,
Attorney-in-Fact, full power and authority to do and perform each and every
act and thing, requisite and necessary to be done in and about the premises,
as fully, to all intents and purposes as he might or could do if personally
present at the doing thereof, with full power of substitution and revocation,
hereby ratifying and confirming all that each of such Attorney-in-Fact or his
substitutes shall lawfully do or cause to be done by virtue hereof.

     This Power of Attorney shall remain in full force and effect until
terminated by the undersigned through the instrumentality of a signed
writing.

     IN WITNESS WHEREOF, Henry H. Goldberg, has hereunto set his hand this
1st day of March, 2002.


                                         /s/ Henry H. Goldberg
                                       -------------------------------------
                                                 Henry H. Goldberg


     I, Priscilla Drevo, a Notary Public in and for said County in the State
of aforesaid, do hereby certify that Henry H. Goldberg, personally known to
me to be the same person whose name is subscribed to the foregoing instrument
appeared before me this day in person and acknowledged that he signed and
delivered said instrument as his own free voluntary act for the uses and
purposes therein set forth.

     Given under my hand and notarial seal this 1st day of March, 2002.


[NOTARY PUBLIC SEAL]                    /s/ Priscilla Drevo
                                       -------------------------------------
                                                 (Notary Public)


My Commission Expires: 12/1/03