@article{KuesterPoetsch1998,
  author    = {K{\"u}ster, H. and P{\"o}tsch, Joachim},
  title     = {{\"O}kosystemwandel in Flußlandschaften Norddeutschlands},
  year      = {1998},
  language  = {de}
}
@article{MuehleBurkartPoetsch1998,
  author    = {M{\"u}hle, Ralf-Udo and Burkart, Michael and P{\"o}tsch, Joachim},
  title     = {On the importance of flooded grassland at the Ramsar site of the lower Havel river valley for waterfowl},
  issn      = {0761-9243},
  year      = {1998},
  language  = {en}
}