Non-linear phonology

Another important consideration is that if we are going to use an HMM based labeller, then it makes sense to use a sound representation system which is amenable to HMM labelling. In general this means adopting a system which represents speech sounds as a linear list, and unfortunately precludes some of the more sophisticated non-linear phonologies described in Section 7.4.3. 

Durand, J. Dependency and Non-Linear Phonology. Croom Helm, 1986. 

Sagey, E. The representation of features and relations in non-linear phonology. PhD thesis, MIT, 1986. 

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