@inproceedings{beyondmodelextractionimitationattackfor,
  title = {Student Surpasses Teacher: Imitation Attack for Black-Box NLP APIs},
  author = {Qiongkai Xu and Xuanli He and Lingjuan Lyu and Lizhen Qu and Gholamreza Haffari},
  year = {2021},
  booktitle = {COLING 2022 10},
  eprint = {2108.13873},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2108.13873v2},
}