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                                                                    EXHIBIT 99.6

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

     GUIDELINES FOR DETERMINING THE PROPER IDENTIFICATION NUMBER TO GIVE THE
PAYER-- Social Security Numbers have nine digits separated by two hyphens: i.e.,
000-00-0000. Employer Identification Numbers have nine digits separated by only
one hyphen: i.e., 00-0000000. The table below will help determine the type of
number to give the payer.



                                              GIVE THE                                                 GIVE THE
          FOR THIS TYPE OF                SOCIAL SECURITY            FOR THIS TYPE OF       EMPLOYER IDENTIFICATION NUMBER
              ACCOUNT:                       NUMBER OF--                  ACCOUNT:                       OF --
- ------------------------------------  ------------------------  --------------------------  -------------------------------
                                                                                   
1.  An individual's account           The individual            8.  Sole proprietorship     The owner (4)
                                                                    account
2.  Two or more individuals (joint    The actual owner of the   9.  A valid trust, estate   The legal entity (Do not furnish
    account)                          account or, if combined       or pension trust        the identifying number of the
                                      funds, any one of the                                 personal representative or
                                      individuals (1)                                       trustee unless the legal entity
                                                                                            itself is not designated in the
                                                                                            account title) (5)
3.  Husband and wife (joint account)  The actual owner of the   10. Corporate account       The corporation
                                      account or, if joint
                                      funds, either person (1)

4.  Custodian account of a minor      The minor (2)             11. Religious,              The organization
    (Uniform Gift to Minors Act)                                    charitable, or
                                                                    educational
                                                                    organization account

5.  Adult and minor (joint account)   The adult or, if the      12. Partnership account     The partnership
                                      minor is the only             held in the name of
                                      contributor, the minor        the business
                                      (1)

6.  Account in the name of guardian   The ward, minor, or       13. Association, club, or   The organization
    or committee for a designated     incompetent person (3)        other tax-exempt
    ward, minor, or incompetent                                     organization
    person

7.a.  The usual revocable saving      The grantor-trustee (1)   14. A broker or             The broker or nominee
      trust account (grantor is                                     registered nominee
      also trustee)

  b.  So-called trust account that    The actual owner (1)      15. Account with the        The public entity
      is not a legal or valid trust                                 Department of
      under State law                                               Agriculture in the
                                                                    name of a public
                                                                    entity (such
                                                                    as a State or local
                                                                    government, school
                                                                    district, or prison)
                                                                    that receives
                                                                    agricultural program
                                                                    payments


- ---------------
(1)  List first and circle the name of the person whose number you furnish.

(2)  Circle the minor's name and furnish the minor's social security number.

(3)  Circle the ward's, minor's or incompetent person's name and furnish such
     person's social security number.

(4)  You must show your individual name, but you may also enter your business
     or "doing business" name. You may use either your Social Security Number
     or Employer Identification Number.

(5)  List first and circle the name of the legal trust, estate, or pension
     trust.

NOTE:    If no name is circled when there is more than one name, the number will
be considered to be that of the first name listed.


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

                                     PAGE 2


OBTAINING A NUMBER

     If you do not have a taxpayer identification number or if you do not know
your number, obtain Form SS-5, Application for Social Security Number 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.

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

     -    A corporation.

     -    A financial institution.

     -    An organization exempt from a tax under Section 501(a), or an
          individual retirement plan or a custodial account under Section
          403(b)(7) if the account satisfies the requirements of Section
          401(F)(2).

     -    The United States or any agency or instrumentality thereof.

     -    A State, the District of Columbia, a possession of the United States,
          or any subdivision or instrumentality thereof.

     -    A foreign government, a political subdivision of a foreign government,
          or any agency or instrumentality thereof.

     -    An international organization or any agency or instrumentality
          thereof.

     -    A registered dealer in securities or commodities registered in the
          U.S. 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 entity registered at all times under the Investment Company Act of
          1940.

     -    A foreign central bank of issue.

     -    A futures commission merchant registered with the Commodity Futures
          Trading Commission.

     -    A person registered under the Investment Advisors Act of 1940 who
          regularly acts as a broker.

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.

     -    Payments of patronage dividends where the amount received is not paid
          in money.

     -    Payments made by certain foreign organizations.

     -    Payments made to a nominee.

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 taxpayer 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 nonresident aliens.

     -    Payments on tax-free covenant bonds under Section 1451.

     -    Payments made by certain foreign corporations.

     -    Payments made to a nominee.

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

Certain payments other than interest, dividends, and patronage dividends, which

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

                                     PAGE 3


are not subject to information reporting are also not subject to backup
withholding. For details, see the regulations under Section 6041, 6041(A)(a),
6045, and 6050A.

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. IRS uses the numbers for identification
purposes. Payers must be given the numbers whether or not recipients are
required to file tax returns. Beginning January 1, 1993, payers must generally
withhold 31% of taxable interest, dividend, 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) FAILURE TO REPORT CERTAIN DIVIDEND AND INTEREST PAYMENTS. -- If you fail to
include any portion of an includible payment for interest, dividends, or
patronage dividends in gross income, such failure will be treated as being due
to negligence and will be subject to a penalty of 5% on any portion of an
under-payment attributable to that failure unless there is clear and convincing
evidence to the contrary.

(3) 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.

(4) CRIMINAL PENALTY FOR FALSIFYING INFORMATION.-- Falsifying certifications or
affirmations may subject you to criminal penalties including fines and/or
imprisonment. FOR ADDITIONAL INFORMATION CONTACT YOUR TAX CONSULTANT OR THE
INTERNAL REVENUE SERVICE.