diff --git a/week5/part-of-speech/notes.md b/week5/part-of-speech/notes.md
index 44ac55e..a9d1e89 100644
--- a/week5/part-of-speech/notes.md
+++ b/week5/part-of-speech/notes.md
@@ -8,4 +8,6 @@ Example: [http://parts-of-speech.info](http://parts-of-speech.info)
 
 [Phrase structure grammar](https://en.wikipedia.org/wiki/Phrase_structure_grammar)
 
-[Parse Tree](https://en.wikipedia.org/wiki/Parse_tree)
\ No newline at end of file
+[Parse Tree](https://en.wikipedia.org/wiki/Parse_tree)
+
+### [pos: fasttag part of speech tagger implementation](https://www.npmjs.com/package/pos)
\ No newline at end of file