@phdthesis{76912,
  author = {A. Wiin-Nielsen and E. Källén},
  title = {Non-linear, low order interactions},
  year = {1979},
  journal = {Seminar on Dynamical Meteorology and Numerical Weather Forecasting, 3-13 September 1979},
  volume = {I},
  pages = {3-33},
  month = {1979},
  publisher = {ECMWF},
  address = {Shinfield Park, Reading},
  language = {eng},
}