Towards error annotation in a learner corpus of Portuguese Iria del Río author Sandra Antunes author Amália Mendes author Maarten Janssen author 2016-11 text Proceedings of the joint workshop on NLP for Computer Assisted Language Learning and NLP for Language Acquisition Elena Volodina editor Gintarė Grigonytė editor Ildikó Pilán editor Kristina Nilsson Björkenstam editor Lars Borin editor LiU Electronic Press Umeå, Sweden conference publication del-rio-etal-2016-towards https://aclanthology.org/W16-6502/ 2016-11 8 17