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"; 
				}
				
				else if (anchor.getAttribute("href") && anchor.getAttribute("rel") == "popup"){
					anchor.target = "_blank";
				}
		} 
} 
		window.onload = externalLinks;