@techreport{Andre-etal93-ppp,
  author	= {Andr{\'e}, Elisabeth and Graf, Winfried H. and Heinsohn, J. and Nebel, Bernhard and Profitlich, H.-J. and Rist, Thomas and Wahlster, Wolfgang},
  title		= {PPP - Personalized Plan-Based Presenter},
  institution	= {DFKI},
  number	= {D-93-5},
  year		= {1993}
}