function abrePopup(urlPage, titulo)
{
    var url = '/indique-amigo.php?urlPage=' + urlPage + '&titulo=' + titulo;
    var width = 330;
    var height = 550;
    var left = parseInt((screen.availWidth/2) - (width/2));
    var top = parseInt((screen.availHeight/2) - (height/2));
    var windowFeatures = "width=" + width + ",height=" + height + ", status, resizable=false, scroolbar=false, left=" + left + ",top=" + top + "screenX=" + left + ",screenY=" + top;

	window.open (url, "mywindow", windowFeatures);
}