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.target = "_blank";
            }
        }
        window.onload = externalLinks;