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") == "nofollow" ||
 anchor.getAttribute("rel") == "external nofollow" ||
 anchor.getAttribute("rel") == "nofollow external" )
 )
 anchor.target = "_blank";
 }
}
window.onload = function() {
 externalLinks();
}