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("rel")) {
         var rel = anchor.getAttribute("rel");
         var external = false;
         if (rel.indexOf(" ") > 0) {
            while (rel.indexOf(" ") > 0 && external == false) {
               if (rel.substr(0, rel.indexOf(" ")) == "external") {
                  external = true;
               }
               rel = rel.substr(rel.indexOf(" ") + 1, rel.length - rel.indexOf(" ") + 1);
            }
         }
         if (rel == "external") {
            external = true;
         }
         if (anchor.getAttribute("href") && external == true) {
            anchor.target = "_blank";
         }
      }
   }
   return;
}