@article{XiaGerhardKuenstleretal.1999,
  author    = {Xia, Zhongfu and Gerhard, Reimund and K{\"u}nstler, Wolfgang and Wedel, Armin and Danz, Rudi},
  title     = {High surface-charge stability of porous polytetrafluoroethylene electret films at room and elvated temperatures},
  year      = {1999},
  language  = {en}
}
@article{GerhardKuenstlerGoerneetal.2000,
  author    = {Gerhard, Reimund and K{\"u}nstler, Wolfgang and G{\"o}rne, Thomas and Pucher, Andreas and Weinhold, Till and Seiß, Martin and Xia, Zhongfu and Wedel, Armin and Danz, Rudi},
  title     = {Porous polytetrafluoroethylene space-charge electrets for piezoelectrical applications},
  year      = {2000},
  language  = {en}
}
@phdthesis{Wedel1992,
  author    = {Wedel, Armin},
  title     = {Untersuchungen zum Dipolschaltverhalten an Polymerfestk{\"o}rpern},
  pages     = {73 Bl. : Ill., graph. Darst. + Thesen (1 Ex.)},
  year      = {1992},
  language  = {de}
}