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  CUSIP NO. 989070503                   13G               
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      NAME OF REPORTING PERSON
 1    S.S. or I.R.S. IDENTIFICATION NO. OF ABOVE PERSON 
                          
        BankAmerica Corporation  
        94-1681731

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      CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP*
 2                                                              (a) [_]
                                                                (b) [X]
                                                 
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      SEC USE ONLY
 3
    

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      CITIZENSHIP OR PLACE OF ORGANIZATION
 4    
      Delaware

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                          SOLE VOTING POWER
                     5     
     NUMBER OF            
                            -0-
      SHARES       -----------------------------------------------------------
                          SHARED VOTING POWER
   BENEFICIALLY      6    
                          
     OWNED BY               -0-
                   -----------------------------------------------------------
       EACH               SOLE DISPOSITIVE POWER
                     7     
    REPORTING                
                            -0-   
      PERSON       -----------------------------------------------------------
                          SHARED DISPOSITIVE POWER
       WITH          8    
                            254,000
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      AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON
 9    
      254,000

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      CHECK BOX IF THE AGGREGATE AMOUNT IN ROW (9) EXCLUDES CERTAIN SHARES*
10                  
 
 
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      PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW 9
11    
      .8%

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      TYPE OF REPORTING PERSON*
12
      HC

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                     *SEE INSTRUCTION BEFORE FILLING OUT!


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