@Misc{ 
  SchShiSpe15,
  author = { Schikorra, Armin and Shieh, Tien-Tsan and Spector, Daniel },
  title = { $L^p$-theory for fractional gradient PDE with VMO coefficients },
  journal = {  },
  year = { 2015 },
  pages = { 10 },
  URL = { http://cvgmt.sns.it/paper/2663/ },
  note = { cvgmt preprint}
}