@article{HanschWallschlaeger1996,
  author    = {Hansch, Petra and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Vocalisation of curassows (Cracidae)},
  year      = {1996},
  language  = {en}
}
@article{HanschWallschlaeger1998,
  author    = {Hansch, Petra and Wallschl{\"a}ger, Hans-Dieter},
  title     = {Untersuchungen zum Fortpflanzungsverhalten von Hokkos im Berliner Zoo},
  year      = {1998},
  language  = {de}
}