diff --git a/sitemap.xml b/sitemap.xml
index 183178e..24d1717 100644
--- a/sitemap.xml
+++ b/sitemap.xml
@@ -14,7 +14,7 @@
 </url>
 <url>
   <loc>http://www.restapitutorial.com/lessons/restquicktips.html</loc>
-  <lastmod>2017-05-12T21:54:09+07:00</lastmod>
+  <lastmod>2017-12-29T21:54:09+07:00</lastmod>
 </url>
 <url>
   <loc>http://www.restapitutorial.com/lessons/httpmethods.html</loc>
@@ -22,7 +22,7 @@
 </url>
 <url>
   <loc>http://www.restapitutorial.com/lessons/restfulresourcenaming.html</loc>
-  <lastmod>2015-02-14T12:55:39+00:00</lastmod>
+  <lastmod>2017-12-29T12:55:39+00:00</lastmod>
 </url>
 <url>
   <loc>http://www.restapitutorial.com/lessons/idempotency.html</loc>