function apri(sName) {
var sRef
var obj
	sRef = 'OpenWindow';
  obj = window.open(sName,sRef,'menubar=no,scrollbars=yes,resizable=yes,status=no,location=no,width=550,height=360');
	obj.focus();
}

function chiudi() {
  window.close();
}

function back() {
  history.back();
}