diff --git a/xmlbuilder2/index.js b/xmlbuilder2/index.js
index 20621bd..e57f6cc 100644
--- a/xmlbuilder2/index.js
+++ b/xmlbuilder2/index.js
@@ -41,3 +41,5 @@ fs.writeFileSync(full_file_name, xml, function(err) {
 });
 
 //FYI: https://stackoverflow.com/a/38829931/15078958
+//FYI: https://www.js-tutorials.com/nodejs-tutorial/how-to-create-xml-file-using-nodejs-xmlbuilder2/
+//FYI: https://oozcitak.github.io/xmlbuilder2/namespaces.html