@incollection{BERNHOLDKALINGLELLEK2012,
  author    = {BERNHOLD, T. and KALING, N. and LELLEK, M.},
  title     = {Produktivit{\"a}tsmessung von Immobilien-Services - empirische Analyse und Status Quo},
  series = {Facility Management Messe 2012 Tagungsband},
  booktitle = {Facility Management Messe 2012 Tagungsband},
  publisher = {VDE Verlag},
  address   = {Berlin, Offenbach},
  isbn      = {978-3-8007-3417-7},
  pages     = {157 -- 170},
  year      = {2012},
  language  = {de}
}