@article{WassermannBudiOhrnbergeretal.1999,
  author    = {Wassermann, Joachim and Budi, E. N. and Ohrnberger, Matthias and Gossler, J.},
  title     = {Long term seismicity and source changes during different activity stages of Mt. Merapi (Indonesia) using a two scale seismic array},
  year      = {1999},
  language  = {en}
}
@phdthesis{Wegler1999,
  author    = {Wegler, Ulrich},
  title     = {Deterministische und statistische Untergrundmodelle des Vulkans Merapi (Java, Indonesien) : eine Analyse k{\"u}nstlich erzeugter seismischer Signale},
  address   = {Potsdam},
  pages     = {vi, 115, XII S. : graph. Darst.},
  year      = {1999},
  language  = {de}
}
@article{WilkeBehrens1999,
  author    = {Wilke, Max and Behrens, Harald},
  title     = {The Dependence of the partitioning of iron and europium between plagioclase and hydrous tonalitic melt on oxygen fugacity},
  year      = {1999},
  language  = {en}
}
@phdthesis{Xiao1999,
  author    = {Xiao, Xiaohui},
  title     = {Experimental study of the rheology of synthetic anorthite-quarz aggregates},
  series = {Scientific technical report / GeoForschungsZentrum Potsdam},
  volume    = {99, 14},
  journal   = {Scientific technical report / GeoForschungsZentrum Potsdam},
  publisher = {GeoForschungsZentrum},
  address   = {Potsdam},
  pages     = {125 S. : graph. Darst., Ill.},
  year      = {1999},
  language  = {en}
}