@Article{ 
  van17,
  author = { van den Berg, Michiel },
  title = { Spectral bounds for the torsion function },
  journal = { Integral Equations and Operator Theory },
  year = { 2017 },
  volume = { 88 },
  pages = { 387-400 },
  URL = { http://cvgmt.sns.it/paper/3717/ },
  note = { cvgmt preprint}
}