@misc{Siebert2005,
  author    = {Stefan Siebert},
  title     = {Global-scale modeling of nitrogen balances at the soil surface},
  booktitle = {Frankfurt hydrology paper ; 2},
  institution = {Geographie},
  series    = {Frankfurt Hydrology Paper},
  number    = {2},
  type      = {workingpaper},
  pages     = {35},
  year        = {2005},
}