@book{FruwirthRoemerRoemeretal.2006,
  author    = {Carl Fruwirth and Theodor Roemer and Theodor Roemer and Theodor Roemer and Theodor Roemer},
  title     = {Die Z{\"u}chtung der vier Hauptgetreidearten und der Zuckerr{\"u}be},
  url       = {http://caliban.mpiz-koeln.mpg.de/~stueber/fruwirth/band4/index.html},
  year      = {2006},
}