@article{learningefficientlexicallyconstrained,
  title = {Learning Efficient Lexically-Constrained Neural Machine Translation with External Memory},
  author = {Ya Li and Xinyu Liu and Dan Liu and Xueqiang Zhang and Junhua Liu},
  year = {2019},
  eprint = {1901.11344},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1901.11344v1},
}