@Article{ 
  fonleopara,
  author = { Fonseca, Irene and Leoni, Giovanni and Paroni, Roberto },
  title = { On lower semicontinuity in $BH^p$ and 2-quasiconvexification },
  journal = { Calc. Var. Partial Differential Equations },
  year = { 2003 },
  volume = { 17 },
  pages = { 283 - 309 },
  URL = { http://cvgmt.sns.it/paper/589/ },
  note = { cvgmt preprint}
}