// JavaScript Document

	function abrir_ventana(url, ancho, alto){
		//var ventana;
		//ventana=window.open("","ventana","");
		//ventana.close();
		var myLeft = (screen.width-ancho)/2;
		var myTop = (screen.height-alto)/2;
			ventana=window.open(url,'ventana','width='+ancho+',height='+alto+', scrollbars=YES, resizable=NO, left='+myLeft+', top=',+myTop+', location=no,directories=no,status=no,toolbar=no,menubar=no');
			ventana.resizeTo(ancho,alto+20)
			ventana.focus();

	}