function externalLinks() {
   if (!document.getElementsByTagName)
      {
            return;
	       }

	          var links = document.getElementsByTagName("a");

		     for (var i = 0; i < links.length; i++) {
			      var link = links[i]; 
			            if (link.getAttribute("href") && link.getAttribute("rel") == "external")
				          {
					           link.target = "_blank"; 
						         }
							    }
							    }

							    window.onload = externalLinks;