//
  // show/hide table of content in the page's content box
  //
 
  function showhide(_hId,_tId)
  {
    // _hId is the id of the div that will be hidden
    // _tId is the id of the text that will change according to the state of the box

    if(document.getElementById(_tId).style.display=="none") {
      document.getElementById(_tId).style.display="block";
      document.getElementById(_hId).firstChild.data="hide";
    } else {
      document.getElementById(_tId).style.display="none";
      document.getElementById(_hId).firstChild.data="show";
    }
  }