function NuevaVentana(documento, ancho, alto, scroll)
{       
        var TapaWindow=null;
        TapaWindow=window.open(documento,'','resizable=yes,menubar=no,location=no,toolbar=no,status=no,scrollbars=' + scroll + ',directories=no,width=' + ancho + ',height=' + alto+ ',top=200,left=200');
        if (TapaWindow){TapaWindow.focus;}
        }