@Article{ 
  MagSteTre16,
  author = { Magnani, Valentino and Stepanov, Eugene and Trevisan, Dario },
  title = { A rough calculus approach to level sets in the Heisenberg group },
  journal = { J. Lond. Math. Soc. },
  year = { 2018 },
  volume = { 97 },
  number = { 3 },
  pages = { 495–522 },
  URL = { http://cvgmt.sns.it/paper/3218/ },
  note = { cvgmt preprint}
}