@article{Karczewska:2015,
  author  = "A. Karczewska and P. Rozmej and Ł. Rutkowski",
  title   = "Problems with energy of waves described by Korteweg - de Vries equation",
  journal = "Annales Universitatis Mariae Curie-Skłodowska. Sectio AAA. Physica",
  volume  = "Vol. 70",
  pages   = "41--54",
  year    = "2015",
}