@Article{ 
  mag02,
  author = { Magnani, Valentino },
  title = { Characteristic points, rectifiability and perimeter measure on stratified groups },
  journal = {  J. Eur. Math. Soc. },
  year = { 2006 },
  volume = { 8 },
  number = { 4 },
  pages = { 585-609 },
  URL = { http://cvgmt.sns.it/paper/1003/ },
  note = { cvgmt preprint}
}