@Misc{ 
  Gra21a,
  author = { Grande, Raffaele },
  title = { Horizontal mean curvature flow and nonlinear PDEs in sub-Riemannian spaces },
  journal = {  },
  year = { 2021 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/6507/ },
  note = { cvgmt preprint}
}