@phdthesis{76806,
  author = {Drasko Vasiljevic and Carla Cardinali and P. Undén},
  title = {ECMWF 3D variational data assimilation of conventional observations},
  year = {1992},
  journal = {Workshop on Variational Assimilation, with special emphasis on Three-dimensional Aspects, 9-12 November 1992},
  pages = {389-436},
  month = {1992},
  publisher = {ECMWF},
  address = {Shinfield Park, Reading},
  language = {eng},
}