@misc{76671,
  author = {Jean-Noël Thépaut and P. Courtier},
  title = {Four-dimensional variational data assimilation using the adjoint of a multilevel primitiveequation model},
  year = {1991},
  journal = {ECMWF Technical Memoranda},
  number = {178},
  pages = {45},
  month = {02/1991},
  publisher = {ECMWF},
  address = {Shinfield Park, Reading},
  url = {https://www.ecmwf.int/node/12693},
  doi = {10.21957/ih1oqpki7},
  language = {eng},
}