function back()
   {
      if (document.referrer.indexOf("author-index") > -1)
         document.write('<a href="../../author-index.html">&larr; Author archive</a>');
      else if (document.referrer.indexOf("results") > -1)
         document.write('<a href="../../results.html">&larr; Results</a>');
      else document.write('<a href="../..">&larr; Category archive</a>');

      document.write('<a href="../../..">&larr; SSC archives</a>');
   }