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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. The taxpayer identification number for an individual is the individual's
Social Security number. Social Security numbers have nine digits separated by
two hyphens: E.G., 000-00-0000. The taxpayer identification number for an entity
is the entity's Employer Identification number. Employer Identification numbers
have nine digits separated by only one hyphen: e.g., 00-0000000. The table below
will help determine the number to give the payer.

<TABLE>
<CAPTION>
------------------------------------------------------       ------------------------------------------------------
<S>                         <C>                              <C>                         <C>
FOR THIS TYPE OF ACCOUNT:   GIVE THE NAME AND SOCIAL         FOR THIS TYPE OF ACCOUNT:   GIVE THE NAME AND EMPLOYER
                            SECURITY NUMBER OF--                                         IDENTIFICATION NUMBER OF--
------------------------------------------------------       ------------------------------------------------------
1. Individual               The individual                   8. Sole proprietorship      The owner(4)

2. Two or more individuals  The actual owner of the          9. A valid trust, estate,   The legal entity (Do not
(joint account)             account or, if combined          or pension trust            furnish the identifying
                            funds, the first                                             number of the personal
                            individual on the                                            representative or trustee
                            account(1)                                                   unless the legal entity
                                                                                         itself is not designated
                                                                                         in the account title.)(5)

3. Husband and wife (joint  The actual owner of the          10. Corporate               The corporation
account)                    account or, if joint
                            funds, either person(1)

4. Custodian account of a   The minor(2)                     11. Association, club,      The organization
minor (Uniform Gift to                                       religious, charitable,
Minors Act)                                                  educational or other tax-
                                                             exempt organization

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

6. Account in the name      The ward, minor, or              13. A broker or registered  The broker or nominee
guardian or committee for   incompetent person(3)            nominee
a designated ward, minor,
or incompetent person

7. a. The usual revocable   The grantor-trustee(1)           14. Account with the        The public entity
savings trust (grantor is                                    Department of Agriculture
also trustee)                                                in the name of a public
b. So-called trust account  The actual owner(1)              entity (such as a state or
that is not a legal or                                       local government, school
valid trust under state                                      district, or prison) that
law                                                          receives agriculture
                                                             program payments
------------------------------------------------------       ------------------------------------------------------
</TABLE>

(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) Show the name of the owner.

(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

SECTION REFERENCES ARE TO THE INTERNAL REVENUE CODE.

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 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.

To complete the Substitute Form W-9, if you do not have a taxpayer
identification number, write "Applied For" in the space for the taxpayer
identification number in Part 1, sign and date the Form, and give it to the
requester. If the requester does not receive your taxpayer identification number
within 60 days, backup withholding, if applicable, will begin and will continue
until you furnish your taxpayer identification number to the requester.

PAYEES EXEMPT FROM BACKUP WITHHOLDING

    The following is a list of payees exempt from backup withholding and for
which no information reporting is required. For interest and dividends, all
listed payees are exempt except item (9). For broker transactions, payees listed
in (1) through (13) and a person registered under the Investment Advisers Act of
1940 who regularly acts as a broker are exempt. Payments subject to reporting
under sections 6041 and 6041A are generally exempt from backup withholding only
if made to payees described in items (1) through (7), except that a corporation
that provides medical and health care services or bills and collects payments
for such services is not exempt from backup withholding or information
reporting. Only payees described in items (2) through (6) are exempt from backup
withholding for barter exchange transactions, patronage dividends, and payments
by certain fishing boat operators.

 (1) A corporation.

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

 (3) The United States or any of its agencies or instrumentalities.

 (4) A State, the District of Columbia, a possession of the United States, or
     any of their political subdivisions or instrumentalities.

 (5) A foreign government or any of its political subdivisions, agencies or
     instrumentalities.

 (6) An international organization or any of its agencies or instrumentalities.

 (7) A foreign central bank of issue.

 (8) A dealer in securities or commodities required to register in the United
     States, the District of Columbia, or a possession of the United States.

 (9) A futures commission merchant registered with the Commodity Futures Trading
     Commission.

(10) A real estate investment trust.

(11) An entity registered at all times during the tax year under the Investment
     Company Act of 1940.

(12) A common trust fund operated by a bank under section 584(a).

(13) A financial institution.

(14) A middleman known in the investment community as a nominee or listed in the
     most recent publication of the American Society of Corporate
     Secretaries, Inc., Nominee List.

(15) A trust exempt from tax under section 664 or described in section 4947.

Payments of dividends and patronage dividends generally not subject to backup
withholding also 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 United
  States and that have at least one nonresident partner.

- Payments of patronage dividends not paid in money.

- Payments made by certain foreign organizations.

- Payments made to a nominee.

Payments of interest generally not 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 organizations.

- Mortgage interest paid by you.

Payments that are not subject to information reporting are also not subject to
backup withholding. For details see sections 6041, 6041A(a), 6042, 6044, 6045,
6049, 6050A and 6050N, and the regulations under such sections.

Exempt payees described above should file Form W-9 to avoid possible erroneous
backup withholding. ENTER YOUR TAXPAYER IDENTIFICATION NUMBER. WRITE "EXEMPT" ON
THE FACE OF THE FORM, SIGN AND DATE THE FORM AND RETURN IT TO THE PAYER.

PRIVACY ACT NOTICE

    Section 6109 requires you to give your correct taxpayer identification
number to persons who must file information returns with the IRS to report
interest, dividends, and certain other income paid to you, mortgage interest you
paid, the acquisition or abandonment of secured property, cancellation of debt,
or contributions you made to an IRA. The IRS uses the numbers for identification
purposes and to help verify the accuracy of your tax return. You must provide
your taxpayer identification number whether or not you are qualified to file a
tax return. 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) CIVIL PENALTY FOR FALSE INFORMATION WITH RESPECT TO WITHHOLDING. If you make
    a false statement with no reasonable basis that results in no backup
    withholding, you are subject to a $500 penalty.

(3) 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