@phdthesis{73825,
  author = {M. Buehner},
  title = {Ensemble-based background-error covariances in variational data assimilation},
  year = {2007},
  journal = {ECMWF Workshop on Flow-dependent aspecyts of data assimilation, 11-13 June 2007},
  pages = {37-46},
  month = {2007},
  publisher = {ECMWF},
  address = {Shinfield Park, Reading},
  language = {eng},
}