@misc{wang2019tree,
  title={Tree Transformer: Integrating Tree Structures into Self-Attention},
  author={Yau-Shian Wang and Hung-Yi Lee and Yun-Nung Chen},
  year={2019},
  eprint={1909.06639},
  archivePrefix={arXiv},
  primaryClass={cs.CL},
  url={https://arxiv.org/abs/1909.06639}
}