@article{Matkowski:1996,
  author  = "J. Matkowski and M. Wróbel",
  title   = "A generalized $a$-Wright convexity and related functional equation",
  journal = "Annales Mathematicae Silesianae",
  volume  = "nr 10",
  pages   = "7--12",
  year    = "1996",
  note    = "Uniwersytet ¦l±ski, Katowice",
}