@article{JMLR:v24:22-1043,
  author  = {Riccardo Grazzi and Massimiliano Pontil and Saverio Salzo},
  title   = {Bilevel Optimization with a Lower-level Contraction: Optimal Sample Complexity without Warm-Start},
  journal = {Journal of Machine Learning Research},
  year    = {2023},
  volume  = {24},
  number  = {167},
  pages   = {1--37},
  url     = {http://jmlr.org/papers/v24/22-1043.html}
}