@article{KlieglMayr1997,
  author    = {Kliegl, Reinhold and Mayr, Ulrich},
  title     = {Kognitive Leistung und Lernpotential im h{\"o}heren Erwachsenenalter},
  isbn      = {3-8017-0532-2},
  year      = {1997},
  language  = {de}
}
@article{VerhaeghenKlieglMayr1997,
  author    = {Verhaeghen, Paul and Kliegl, Reinhold and Mayr, Ulrich},
  title     = {Sequential and coordinative complexity in time-accurary functions for mental arithmetic},
  year      = {1997},
  language  = {en}
}