@inproceedings{GoettscheSchwarzerRoetheretal.2009,
  author    = {G{\"o}ttsche, Joachim and Schwarzer, Klemens and R{\"o}ther, Sascha and Jellinghaus, Sabine and Helten, G. and Wittmann, R.},
  title     = {Efficient daylighting, heating and shading with rooflight heliostats},
  series = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings},
  booktitle = {Renewables in a changing climate : from Nano to Urban Scale : CISBAT 2009 : 2-3 September 2009, EPFL, Lausanne, Switzerland : proceedings},
  publisher = {Ecole Polytechnique F{\´e}d{\´e}rale de Lausanne},
  address   = {Lausanne},
  pages     = {243 -- 246},
  year      = {2009},
  language  = {en}
}
@article{WittmannFortezza1992,
  author    = {Wittmann, Klaus and Fortezza, R.},
  title     = {Telescience opportunities in the precursor flights},
  series = {Space Technology - Industrial and Commercial Applications. 13 (1992), H. 2},
  journal   = {Space Technology - Industrial and Commercial Applications. 13 (1992), H. 2},
  isbn      = {0892-9270},
  pages     = {221 -- 226},
  year      = {1992},
  language  = {en}
}
@article{WittmannGillessenOttoetal.1996,
  author    = {Wittmann, Klaus and Gillessen, F. and Otto, G. and R{\"o}stel, R.},
  title     = {Undercooling and solidification of metallic melts suspended in a non-nucleating matrix: Experiment NUCAL of the German Spacelab Mission D-2},
  series = {Acta Astronautica. 38 (1996), H. 1},
  journal   = {Acta Astronautica. 38 (1996), H. 1},
  isbn      = {0094-5765},
  pages     = {63 -- 68},
  year      = {1996},
  language  = {en}
}
@article{WittmannKehrWillnecker2000,
  author    = {Wittmann, Klaus and Kehr, J. and Willnecker, R.},
  title     = {Decentralized Payload Operations Concept for Columbus},
  year      = {2000},
  language  = {en}
}