@Article{ 
  LeLeMoVi13,
  author = { Le Donne, Enrico and Leonardi, Gian Paolo and Monti, Roberto and Vittone, Davide },
  title = { Extremal polynomials in stratified groups },
  journal = { Comm. Anal. and Geom. },
  year = { 2018 },
  doi = { http://dx.doi.org/10.4310/CAG.2018.v26.n4.a3 },
  volume = { 26 },
  pages = { 723–757 },
  URL = { http://cvgmt.sns.it/paper/2207/ },
  note = { cvgmt preprint}
}