The main part-of-speech tagging tool used is RDRPOSTagger:

	Copyright (C) 2013-2015 by Dat Quoc Nguyen, Dai Quoc Nguyen, Dang Duc Pham and Son Bao Pham	
	RDRPOSTagger's website: http://rdrpostagger.sourceforge.net/
	
This version of RDRPOSTagger has been updated to work in Python 3, along with other minor changes.
Original models and new models (e.g., RDR and DICT files) can be found in the main data directory.