@Misc{ 
  crafragaz04,
  author = { Crasta, Graziano and Fragalà, Ilaria and Gazzola, Filippo },
  title = { Some estimates for the torsional rigidity of composite rods },
  journal = { Math. Nachr. },
  year = { 2004 },
  pages = {  },
  URL = { http://cvgmt.sns.it/paper/1473/ },
  note = { cvgmt preprint}
}