Exhibit (a)(6)

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

Guidelines for Determining the Proper Identification Number for the Payee (You) 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 number to give the payer.

For this type of account:	Give the name and SOCIAL SECURITY number of—
1. An individual’s account	The individual
2. Two or more individuals (joint account)	The actual owner of the account or, if combined funds, the first individual on the account(1)
3. Custodian account of a minor (Uniform Gift to Minors Act)	The minor(2)
4. a. The usual revocable savings trust (grantor is also trustee)	The grantor-trustee(1)
b. So-called trust account that is not a legal or valid trust under State law	The actual owner(1)
5. Sole proprietorship for single-owner account	The owner(3)
For this type of account:	Give the EMPLOYER IDENTIFICATION number of—
6. A valid trust, estate, or pension trust	The legal entity(4)
7. Corporate or LLC electing corporate status on Form 8832 account	The corporation
8. Partnership or multi-member LLC account held in the name of the business	The partnership
9. Association, club, or tax-exempt organization account	The organization
10. A broker or registered nominee	The broker or nominee
11. Account with the Department of Agriculture in the name of a public entity (such as a State or local government, school district, or prison) that receives agricultural program payments	The public entity

(1) List first and circle the name of the person whose number you furnish. If only one person has a social security number, that person’s number must be furnished.

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

(3) Show the name of the owner. You must show your individual name, but you may also enter your business or “doing business as” name. Either your social security number or employer identification number (if you have one) may be used.

(4) List first and circle the name of the legal trust, estate, or pension trust. (Do not furnish the taxpayer identification number of the personal representative or trustee unless the legal entity itself is not designated in the account title.)

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

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Obtaining a Number

If you do not have a taxpayer identification number (“TIN”) you should apply for one immediately. You may obtain Form SS-5, Application for a Social Security Card, at the local office of the Social Security Administration. You may obtain Form SS-4, Application for Employer Identification Number, or Form W-7, Application for IRS Individual Taxpayer Identification Number, from the Internal Revenue Service by calling 1-800-TAX-FORM (1-800-829-3676) or from the IRS’s Internet website at www.irs.gov. If you do not have a TIN, write “Applied For” in the space for the TIN.

Payees Exempt from Backup Withholding

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

• A corporation.

• A financial institution.

• An organization exempt from tax under Section 501(a) of the Internal Revenue Code of 1986, as amended (the “Code”), or an individual retirement account, or a custodial account under Section 403(b)(7) of the Code if the account satisfies the requirements of Section 401(f)(2) of the Code.

• 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.

• An international organization or any agency or instrumentality thereof.

• A foreign government or any political subdivision, agency or instrumentality thereof.

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

• A real estate investment trust.

• A common trust fund operated by a bank under Section 584(a) of the Code.

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

• A foreign central bank of issue.

Certain other payees may be exempt from either dividend and interest payments or broker transactions. You should consult your tax advisor to determine whether you might be exempt from backup withholding. Exempt payees described above should file the substitute Form W-9 to avoid possible erroneous backup withholding. Complete the substitute Form W-9 as follows:

ENTER YOUR TAXPAYER IDENTIFICATION NUMBER, WRITE “EXEMPT” ACROSS THE FACE OF THE FORM, SIGN AND DATE THE FORM AND RETURN THE FORM TO THE PAYER.

IF YOU ARE A NONRESIDENT ALIEN OR FOREIGN ENTITY NOT SUBJECT TO BACKUP WITHHOLDING, GIVE THE PAYER THE APPROPRIATE COMPLETED FORM W-8.

Privacy Act Notice—Section 6109 of the Code requires you to provide your correct taxpayer identification number to payers who must report the payments to the IRS. The IRS uses the number for identification purposes and may also provide this information to various government agencies for tax enforcement or litigation purposes. Payers must be given the numbers whether or not recipients are required to file tax returns. Payers must generally withhold 28% 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.

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Penalties

(1) Penalty for Failure to Furnish Taxpayer Identification Number—If you fail to furnish your correct 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.

FOR ADDITIONAL INFORMATION,

CONTACT YOUR TAX CONSULTANT OR

THE INTERNAL REVENUE SERVICE.

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