@inproceedings{ubo:14808,
  author = {Ziegler, J. and Hase, H. and Caloyannis, E.},
  chapter = {},
  title = {Prozess- und Kooperationsunterstützung in Intra- und Internet},
  year = {1998},
  publisher = {DLR e.V.},
  booktitle = {Bonn 24.11.1998; Bonn 24.11.1998}
}


@inproceedings{ubo:14809,
  author = {Sutcliffe, A.G. and Ziegler, J. and Johnson, P.},
  chapter = {},
  year = {1998},
  publisher = {Kluwer Academic Publishers},
  booktitle = {},
  title = {Designing Effective and Usable Multimedia Systems}
}