@article{Matkowski:2011,
  author  = "J. Matkowski",
  title   = "Quotient mean, its invariance with respect to a quasi-arithmetic mean-type mapping, and some applications",
  journal = "Aequationes Mathematicae",
  volume  = "Vol. 82",
  number  = "no 3",
  pages   = "247--253",
  year    = "2011",
}