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 ## External Papers
 
+[A tutorial on hidden Markov models and selected applications in speech recognition](http://luthuli.cs.uiuc.edu/~daf/courses/Signals%20AI/Papers/HMMs/0.pdf)
+
 [Weighted Finite-State Transducers in Speech Recognition](http://www.cs.nyu.edu/~mohri/pub/csl01.pdf)
 
 [Decoding speech in the presence of other sources](http://www.ee.columbia.edu/~dpwe/pubs/BarkCE05-sfd-spcomm.pdf)