@misc{FreydankSiebert2008,
  author    = {Katharina Freydank and Stefan Siebert},
  title     = {Towards mapping the extent of irrigation in the last century : time series of irrigated area per country},
  booktitle = {Frankfurt hydrology paper ; 8},
  institution = {Geowissenschaften},
  series    = {Frankfurt Hydrology Paper},
  number    = {8},
  type      = {workingpaper},
  pages     = {46},
  year        = {2008},
}