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          Volume 2, Issue 3, Article 37 | 
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             $L^p-$Improving Properties for Measures on $\mathbb{R}^{4}$ Supported on Homogeneous Surfaces in Some Non Elliptic Cases
 
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          Authors:  | 
          E. Ferreyra, T. Godoy, M. Urciuolo,  | 
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          Keywords: 
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          Singular Measures, $L^p$-Improving, Convolution Operators. | 
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          Date Received: 
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          08/01/01 | 
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          Date Accepted: 
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          05/06/01 | 
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          Subject Codes: | 
           
             42B20,42B10. 
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          Editors:  | 
          Lubos Pick,   | 
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          Abstract: | 
           
              In this paper we study convolution operators   with measures   in   of the form   where   is the unit ball of  , and   is a homogeneous polynomial function. If   vanishes only on a finite union of lines, we prove that   is bounded from   into   if   belongs to certain explicitly described trapezoidal region.
             
          
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