@article{kaysilvester2001,
  title = "The reliability of local error estimators for convection-diffusion equations",
  author = "D. Kay and David Silvester",
  year = "2001",
  journal = "IMA J. Num. Anal.",
  pages = "107--122",
  volume = "21",
  doi = "10.1093/imanum/21.1.107",
}