@inproceedings{proqastructuralpromptbasedpretraining1,
  title = {ProQA: Structural Prompt-based Pre-training for Unified Question Answering},
  author = {Wanjun Zhong and Yifan Gao and Ning Ding and Yujia Qin and Zhiyuan Liu and Ming Zhou and Jiahai Wang and Jian Yin and Nan Duan},
  year = {2022},
  booktitle = {NAACL 2022 7},
  eprint = {2205.04040},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2205.04040v2},
}