@article{KohLeuL:07a,
  journal = {Nonlinear Analysis Series A: Theory, Methods \& Applications},
  volume = {66},
  title = {Approximate fixed points of nonexpansive functions in product
           spaces},
  author = {Kohlenbach, Ulrich and Leu\c stean, Lauren\c tiu},
  year = 2007,
  pages = {806--818},
  number = {4},
}