@article{Dittler,
  author    = {Ullrich Dittler},
  title     = {Das Allesk{\"o}nner-Objektiv: Das 89/500 Telephoto Lens/Scope von Kowa im Test},
  series = {Interstellarum: Zeitschrift f{\"u}r praktische Astronomie},
  number    = {99},
  pages     = {58 -- 61},
  language  = {de}
}