anchor.diff:              </a>
             </div>
           </div>
  +
  + 
  + 
         </div>
   
       </div>
  
positive.code:         <div class="col-sm-3">
            <div class="thumbnail">
              <a href="*/http://slacvm.slac.stanford.edu/FIND/slac.html">
                <img alt="SLAC homepage 1992-1995 Timemap" src="/images/featured_sites/slac_1994.jpg">
                <div class="caption">
                  <h3>SLAC homepage 1992-1995</h3>
  
negative.code:         <div class="col-sm-3">
            <div class="thumbnail">
              <a href="19911206000000/http://slacvm.slac.stanford.edu/FIND/default.html">
                 <img alt="SLAC first webpage" src="/images/featured_sites/slac_1991.jpg">
                <div class="caption">
                  <h3>SLAC first webpage</h3>
                </div>
  