@inproceedings{wu-matsumoto-2015-improved,
    title = "An Improved Hierarchical Word Sequence Language Model Using Directional Information",
    author = "Wu, Xiaoyi  and
      Matsumoto, Yuji",
    editor = "Zhao, Hai",
    booktitle = "Proceedings of the 29th Pacific Asia Conference on Language, Information and Computation",
    month = oct,
    year = "2015",
    address = "Shanghai, China",
    url = "https://preview.aclanthology.org/jlcl-multiple-ingestion/Y15-1051/",
    pages = "449--454"
}