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          Volume 7, Issue 3, Article 86 | 
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             Cesáro Means of $N$-multiple Trigonometric Fourier Series
 
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          Authors:  | 
          Ushangi Goginava,  | 
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          Keywords: 
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          Trigonometric system, Cesáro means, Summability. | 
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          Date Received: 
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          06/03/06 | 
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          Date Accepted: 
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          08/03/06 | 
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          Subject Codes: | 
           
             42B08. 
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          Editors:  | 
          Laszlo Leindler,   | 
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          Abstract: | 
           
              Zhizhiashvili proved sufficient conditions for the Cesáro summability by negative order of  multiple trigonometric Fourier series in the space   . In this paper we show that this condition cannot be improved.
             
          
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