diff --git a/public/js/ajax.js b/public/js/ajax.js
index 2af0bc0..72ef1f7 100644
--- a/public/js/ajax.js
+++ b/public/js/ajax.js
@@ -3,6 +3,8 @@
 // https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest
 // https://developer.mozilla.org/en-US/docs/Web/API/XMLHttpRequest/Using_XMLHttpRequest
 // r.addEventListener("progress", updateProgress, false);
+// http://www.javascriptkit.com/javatutors/loadjavascriptcss.shtml
+// http://stackoverflow.com/questions/6112744/load-javascript-on-demand
 var Ajax = {
   getJSON : function (url, onload) {
     var r = new XMLHttpRequest();