@inproceedings{levitan-etal-2011-entrainment,
    title = "Entrainment in Speech Preceding Backchannels.",
    author = "Levitan, Rivka  and
      Gravano, Agust{\'i}n  and
      Hirschberg, Julia",
    editor = "Lin, Dekang  and
      Matsumoto, Yuji  and
      Mihalcea, Rada",
    booktitle = "Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies",
    month = jun,
    year = "2011",
    address = "Portland, Oregon, USA",
    publisher = "Association for Computational Linguistics",
    url = "https://preview.aclanthology.org/fix-sig-urls/P11-2020/",
    pages = "113--117"
}