function externalLinks() {
	if (!document.getElementsByTagName) return;
	var anchors = document.getElementsByTagName("a");
	for (var i=0; i < anchors.length; i++) {
		var anchor = anchors[i];
		if (
			anchor.getAttribute("href") && (
			anchor.getAttribute("rel") == "external" ||
			anchor.getAttribute("rel") == "external nofollow" ||
			anchor.getAttribute("rel") == "nofollow external" ||
            anchor.getAttribute("class") == "thumb external" ||
            anchor.getAttribute("class") == "external")
			) {
				anchor.className += ' external';
				anchor.target = "_blank";
                anchor.title = "Ir a enlace en ventana nueva";
			}
	}
}
window.onload = function() {
	externalLinks();
}