@Article{ 
  AgrBarRiz13,
  author = { Agrachev, Andrei and Barilari, Davide and Rizzi, Luca },
  title = { Curvature: a variational approach },
  journal = { Memoirs of the AMS },
  year = { 2018 },
  doi = { 10.1090/memo/1225 },
  volume = { 256 },
  number = { 1225 },
  pages = { 142 },
  URL = { http://cvgmt.sns.it/paper/2172/ },
  note = { cvgmt preprint}
}