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function toggle(object) {
  if (document.getElementById) {
    if (document.getElementById(object).style.visibility == 'visible') {
      document.getElementById(object).style.visibility = 'hidden';
      document.getElementById(object).style.display='none';
    } else {
      document.getElementById(object).style.visibility = 'visible';
      document.getElementById(object).style.display='block';
    }
  }

  else if (document.layers && document.layers[object] != null) {
    if (document.layers[object].visibility == 'visible' ||
        document.layers[object].visibility == 'show' )
      document.layers[object].visibility = 'hidden';
    else
      document.layers[object].visibility = 'visible';
  }

  else if (document.all) {
    if (document.all[object].style.visibility == 'visible')
      document.all[object].style.visibility = 'hidden';
    else
      document.all[object].style.visibility = 'visible';
  }

}