diff --git a/README.md b/README.md
index fe216a5..03ecf43 100644
--- a/README.md
+++ b/README.md
@@ -145,6 +145,8 @@ The HTML5 doctype is require to work correctly.
 
 [More information](http://www.w3schools.com/tags/tag_doctype.asp)
 
+For a HTML Doctype reference see [here](https://www.scaler.com/topics/html/doctype-html/)
+
 ## Support
 
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