@Article{ 
  BorKli22,
  author = { Borza, Samuël and Klingenberg, Wilhelm },
  title = { Local non-injectivity of the exponential map at critical points in  sub-Riemannian geometry },
  journal = { Nonlinear Analysis },
  year = { 2024 },
  doi = { https://doi.org/10.1016/j.na.2023.113421 },
  volume = { 239 },
  pages = { 113421 },
  URL = { http://cvgmt.sns.it/paper/6741/ },
  note = { cvgmt preprint}
}