@article{Jarczyk:2006,
  author  = "J. Jarczyk and J. Matkowski",
  title   = "Invariance in the class of weighted quasi-arithmetic means",
  journal = "Annales Polonici Mathematici",
  volume  = "Vol. 88",
  number  = "no 1",
  pages   = "39--51",
  year    = "2006",
}