function seturl(ref, action) {
  var tmp = '' 
  var len = document.sort_form.selected_items.length;
  if (len) {
    var i = 0;
    while (i<len) {
      if (document.sort_form.selected_items[i].checked) {
	tmp = document.sort_form.selected_items[i].value;
      }
      i++;
    }
  } else {
    tmp = document.sort_form.selected_items.value;
  }
  if (tmp == '') {
    alert(su_msg);
    return false;
  }
  else {
    window.location=ref+"?f="+action+"&i="+tmp;
    return true
  } 
}