@article{Matkowski:2013,
  author  = "J. Matkowski",
  title   = "Invariance of the Bajraktareviĉ means with respect to the Beckenbach-Gini means",
  journal = "Mathematica Slovaca",
  volume  = "Vol. 63",
  number  = "no. 3",
  pages   = "493--502",
  year    = "2013",
}