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                                                                     EXHIBIT 4.7

            GUIDELINES FOR CERTIFICATION OF TAXPAYER IDENTIFICATION
                         NUMBER ON SUBSTITUTE FORM W-9


OBTAINING A NUMBER

     If you do not have a taxpayer identification number or you don't know your
number, obtain Form SS-5, Application for a Social Security Card, or Form SS-4,
Application for Employer Identification Number, at the local office of the
Social Security Administration or the Internal Revenue Service (the "IRS") and
apply for a number.  You may also obtain Form SS-4 by calling the IRS at
1-800-TAX-FORM.

PAYEES EXEMPT FROM BACKUP WITHHOLDING

     Payees specifically exempted from backup withholding on ALL payments
include the following:

     .   An organization exempt from tax under section 501(a), or an individual
         retirement account.
     .   The United States or any wholly-owned agency or instrumentality
         thereof.
     .   A State, the District of Columbia, a possession of the United States or
         any political subdivision or wholly-owned agency or instrumentality
         thereof.
     .   A foreign government, a political subdivision of a foreign government,
         or any wholly-owned agency or instrumentality thereof.
     .   An international organization or any wholly-owned agency, or
         instrumentality thereof.

     Payees specifically exempted from backup withholding on interest and
dividend payments include the following:

     .   A corporation.
     .   A financial institution.
     .   A dealer in securities or commodities required to register in the U.S.,
         the District of Columbia, or a possession of the U.S.
     .   A real estate investment trust.
     .   A common trust fund operated by a bank under section 584(a).
     .   An exempt charitable remainder trust, or a non-exempt trust described
         in section 4947.
     .   An entity registered at all times during the tax year under the
         Investment Company Act of 1940.
     .   A foreign central bank of issue.
     .   A middleman known in the investment community as a nominee or who is
         listed in the most recent publication of the American Society of
         Corporate Secretaries, Inc. Nominee List.

     Payments of dividends and patronage dividends not generally subject to
backup withholding include the following:

     .   Payments to nonresident aliens subject to withholding under
         section 1441.
     .   Payments to partnerships not engaged in a trade or business in the U.S.
         and which have at least one nonresident partner.
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     .   Payments of patronage dividends not paid in money.
     .   Payments made by certain foreign organizations.
     .   Section 404(k) payments made by an ESOP.

     Payments of interest not generally subject to backup withholding include
the following:

     .   Payments of interest on obligations issued by individuals. Note: You
         may be subject to backup withholding if this interest is $600 or more
         and is paid in the course of the payer's trade or business and you have
         not provided your correct identification number to the payer.
     .   Payments of Tax-exempt interest (including exempt-interest dividends
         under section 852).
     .   Payments described in Section 6049(b) (5) to non-resident aliens.
     .   Payments on tax-free covenant bonds under section 1451.
     .   Payments made by certain foreign organizations.

     Exempt payees described above should file the Substitute Form W-9 to avoid
possible erroneous backup withholding.  FILE THE SUBSTITUTE FORM W-9 WITH THE
PAYER.  FURNISH YOUR TAXPAYER IDENTIFICATION NUMBER, CHECK THE BOX MARKED
"EXEMPT" IN PART II OF THE SUBSTITUTE FORM W-9 AND RETURN IT TO THE PAYER.

     Certain payments other than dividends that are not subject to information
reporting are also not subject to backup withholding.  For details, see sections
6041, 6041A, 6045, 605A, 6050N and the regulations thereunder.

     PRIVACY ACT NOTICE--Section 6109 requires most recipients of dividend,
interest, or other payments to give taxpayer identification numbers to payers
who must report the payments to IRS.  The IRS uses the numbers for
identification purposes and to help verify the accuracy of tax returns.  The IRS
also may provide this information to the Department of Justice for civil and
criminal litigation and to cities, states, and the District of Columbia to carry
out their tax laws.  Payers must be given the numbers whether or not recipients
are required to file tax returns.  Payers must generally withhold 31% of taxable
interest, dividends, and certain other payments to a payee who does not furnish
a taxpayer identification number to a payer.  Certain penalties may also apply.

PENALTIES

     (1)  Penalty for Failure to Furnish Taxpayer Identification Number.  If you
fail to furnish your taxpayer identification number to a payer, you are subject
to a penalty of $50 for each such failure unless your failure is due to
reasonable cause and not to willful neglect.

     (2)  Civil Penalty for False Information with Respect to Withholding.  If
you make a false statement with no reasonable basis which results in no
imposition of backup withholding, you are subject to a penalty of $500.

     (3)  Criminal Penalty For Falsifying Information.  Willfully falsifying
certifications or affirmations may subject you to criminal penalties including
fines and/or imprisonment.

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