function openWindow (URL) {
	var winL = Math.round((screen.width) / 2) - 200;
	var winT = Math.round((screen.height) / 2) - 210;

	win = window.open (URL,'popup','height=400,width=400,top='+winT+',left='+winL+',resizable=yes,toolbar=no,scrollbars=yes');
}