<b:widget id='Attribution1' locked='true' title='' type='Attribution'>
            <b:includable id='main'>
    <b:if cond='data:feedbackSurveyLink'>
      <div class='mobile-survey-link' style='text-align: center;'>
        <data:feedbackSurveyLink/>
      </div>
    </b:if>

    <div class='widget-content' style='text-align: center;'>
      <b:if cond='data:attribution != &quot;&quot;'>
       <data:attribution/>
      </b:if>
    </div>

    <b:include name='quickedit'/>
  </b:includable>
          </b:widget>

More at:
http://swapniltech.blogspot.com/2012/06/remove-powered-by-blogger-from-your.html

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