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CUSIP No. 989070107                                       Page  4  of  4  Pages



ITEM 5.  OWNERSHIP OF FIVE PERCENT OR LESS OF A CLASS.

          Applicable
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ITEM 6.  OWNERSHIP OF MORE THAN FIVE PERCENT ON BEHALF OF ANOTHER PERSON.

          Not Applicable
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ITEM 7.  IDENTIFICATION AND CLASSIFICATION OF THE SUBSIDIARY WHICH ACQUIRED
         THE SECURITY BEING REPORTED ON BY THE PARENT HOLDING COMPANY.

         The reporting person is the parent company of (i) Trust Company of the
         West, a California corporation and a bank as defined in Section 3(a)(6)
         of the Securities Exchange Act of 1934 ("TCW"), (ii) TCW Asset
         Management Company, a California corporation and an Investment Adviser
         registered under Section 203 of the Investment Advisers Act of 1940,
         and (iii) TCW Funds Management, Inc., a California corporation and an
         Investment Adviser registered under Section 203 of the Investment
         Advisers Act of 1940.

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ITEM 8.  IDENTIFICATION AND CLASSIFICATION OF MEMBERS OF THE GROUP
          Not Applicable
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ITEM 9.  NOTICE OF DISSOLUTION OF GROUP
          Not Applicable
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ITEM 10. CERTIFICATION

    By signing below I certify  that,  to the best of my  knowledge and belief,
the  securities  referred to above  were  acquired in the  ordinary  course  of
business and were not acquired for the purpose of and do not have the effect of
changing or  influencing the  control of the issuer of such securities and were
not acquired in  connection with or as a participation in any  transaction
having such purposes or effect.

                                  SIGNATURE:

    After  reasonable  inquiry and to the  best of my  knowledge and  belief, I
certify that the  information set forth in this statement is true, complete and
correct.
                                       January 21, 1995
                                       ----------------------------------------
                                       (Date)
                                       /s/ Mohan V. Phansalkar
                                       ----------------------------------------
                                       (Signature)
                                       MOHAN V. PHANSALKAR,
                                       ASSISTANT VICE PRESIDENT - LEGAL
                                       ----------------------------------------
                                       (Name/Title)