@Article{ 
  MetPalRha6,
  author = { Metafune, Giorgio and Pallara, Diego and Rhandi, Abdelaziz },
  title = { Kernel Estimates for Schroedinger Operators },
  journal = { J. Evol. Equ. },
  year = { 2006 },
  volume = { 6 },
  pages = { 433-457 },
  URL = { http://cvgmt.sns.it/paper/2489/ },
  note = { cvgmt preprint}
}