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README.md

@@ -2,16 +2,18 @@
 
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-pysptk is a python wrapper for the [Speech Signal Processing Toolkit (SPTK)](http://sp-tk.sourceforge.net/), which provides a lot of functionalities for speech signal processing such as linear prediction analysis, mel-cepstrum analysis, generalized cepstrum analysis and mel-generalized cepstrum analysis to name a few. See the original project page for more details.
+pysptk is a python wrapper for [Speech Signal Processing Toolkit (SPTK)](http://sp-tk.sourceforge.net/), which provides a lot of functionalities for speech signal processing such as linear prediction analysis, mel-cepstrum analysis, generalized cepstrum analysis and mel-generalized cepstrum analysis to name a few. See the original project page for more details.
 
 
 **NOTE**: pysptk is based on a modified version of SPTK ([r9y9/SPTK](https://github.com/r9y9/SPTK)).
 
 ## Documentation
 
-A reference manual of the SPTK can be found at http://sp-tk.sourceforge.net/.
+- [pysptk documentation](http://pysptk.readthedocs.org/)
+- [A reference manual of SPTK](http://sp-tk.sourceforge.net/)
 
 ## Demonstration notebook