Collins, Michael. 2002. ‘Discriminative Training Methods for Hidden Markov Models’. In Proceedings of the ACL-02 Conference on Empirical Methods in Natural Language Processing  - EMNLP ’02, 1–8. Association for Computational Linguistics. https://doi.org/10.3115/1118693.1118694.
Jurafsky, Dan, and James H. Martin. 2009. Speech and Language Processing: An Introduction to Natural Language Processing, Computational Linguistics, and Speech Recognition. 2nd ed. Vol. Prentice Hall series in artificial intelligence. Upper Saddle River, N.J.: Pearson Prentice Hall.
Smith, Noah Ashton. 2011. Linguistic Structure Prediction. Vol. Synthesis lectures on human language technologies. San Rafael, Calif: Morgan & Claypool. http://dx.doi.org/10.2200/S00361ED1V01Y201105HLT013.
‘Stat NLP Book’. n.d. https://github.com/uclmr/stat-nlp-book.