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README.md

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 Helper library for easy usp communication using mqtt over tcp or ws.
 
-[USP Reference](https://usp-data-models.broadband-forum.org/tr-181-2-13-0-usp.html)
+* [API documentation for usp-js](https://iopsys.se/usp-js/index.html)
+* [BBF's USP reference documentation](https://usp-data-models.broadband-forum.org/tr-181-2-13-0-usp.html)
 
 # Installation
 `npm install usp-js`