@misc{73792,
  author = {F. Bouttier and G.A. Kelly},
  title = {Observing systems experiments in the ECMWF 4D-Var data assimilation system},
  year = {2001},
  journal = {ECMWF Technical Memoranda},
  number = {313},
  month = {02/2001},
  publisher = {ECMWF},
  address = {Shinfield Park, Reading},
  url = {https://www.ecmwf.int/node/8351},
  doi = {10.21957/ohibz4sq2},
  language = {eng},
}