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CUSIP No. 989070107 13G Page 2 of 4 Pages
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(1) Names of Reporting Persons
S.S. or I.R.S. Identification No. of Above Person
THE TCW GROUP, INC.
(FORMERLY KNOWN AS TCW MANAGEMENT COMPANY)
95-3703295
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(2) Check the Appropriate Box if a Member (a) / /
of a Group* (b) / /
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(3) SEC Use Only
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(4) Citizenship or Place of Organization
NEVADA
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Number of Shares (5) Sole Voting
Beneficially Power 1,171,223
Owned by --------------------------------------------------
Each Reporting (6) Shared Voting
Person With Power 0
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(7) Sole Dispositive
Power 1,171,223
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(8) Shared Dispositive
Power 0
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(9) Aggregate Amount Beneficially Owned by Each Reporting Person
1,171,223
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(10) Check Box if the Aggregate Amount in Row (9) Excludes Certain Shares*
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(11) Percent of Class Represented by Amount in Row (9)
3.7%
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(12) Type of Reporting Person*
HC
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