@book{Rutschke1997,
  author    = {Rutschke, Erich},
  title     = {Adler im Aufwind : See-, Fisch- und Schreiadler zwischen Spree und Ostsee ; verfemt - verfolgt - gesch{\"u}tzt},
  publisher = {Stapp},
  address   = {Berlin},
  pages     = {136 S.},
  year      = {1997},
  language  = {de}
}
@book{Rutschke1997,
  author    = {Rutschke, Erich},
  title     = {Wildg{\"a}nse : Lebensweise - Schutz - Nutzung},
  publisher = {Parey},
  address   = {Berlin},
  pages     = {260 S.},
  year      = {1997},
  language  = {de}
}
@book{Rutschke1998,
  author    = {Rutschke, Erich},
  title     = {Der Kormoran : Biologie, {\"O}kologie, Schadabwehr},
  publisher = {Parey},
  address   = {Berlin},
  pages     = {161 S.},
  year      = {1998},
  language  = {de}
}