@InProceedings{gebre-EtAl:2013:BEA8,
  author    = {Gebre, Binyam Gebrekidan  and  Zampieri, Marcos  and  Wittenburg, Peter  and  Heskes, Tom},
  title     = {Improving Native Language Identification with TF-IDF Weighting},
  booktitle = {Proceedings of the Eighth Workshop on Innovative Use of NLP for Building Educational Applications},
  month     = {June},
  year      = {2013},
  address   = {Atlanta, Georgia},
  publisher = {Association for Computational Linguistics},
  pages     = {216--223},
  url       = {http://www.aclweb.org/anthology/W13-1728}
}