Tugkan Batu Sudipto Guha Sampath Kannan Inferring Mixtures of Markov Chains. 186-199 http://springerlink.metapress.com/openurl.asp?genre=article&issn=0302-9743&volume=3120&spage=186 2004 conf/colt/2004 COLT db/conf/colt/colt2004.html#BatuGK04