@article{Matkowski:1978,
  author  = "J. Matkowski and R. Węgrzyk",
  title   = "On equivalence of some fixed point theorems for self-mappings of metrically convex space",
  journal = "Bolletino dell Unione Matematica Italiana. A : Serie V",
  volume  = "Vol. 15",
  number  = "no 2",
  pages   = "359--369",
  year    = "1978",
}