@Article{ 
  Rad15,
  author = { Radici, Emanuela },
  title = { A planar Sobolev extension theorem for piecewise linear homeomorphisms },
  journal = { Pacific Journal of Mathematics },
  year = { 2016 },
  volume = { 238 },
  number = { 2 },
  pages = { 405-418 },
  URL = { http://cvgmt.sns.it/paper/2743/ },
  note = { cvgmt preprint}
}