@article{lowerboundsandacceleratedalgorithmsfor,
  title = {Lower Bounds and Accelerated Algorithms for Bilevel Optimization},
  author = {Kaiyi Ji and Yingbin Liang},
  year = {2021},
  eprint = {2102.03926},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/2102.03926v4},
}