Guizzadi, Renata S. S. Aroyo, Lora, Wagner, Gerd summery 2003 knowledge management collaborative learning environments agent-oriented modeling case study Guizzadi, Renata S. S. Aroyo, Lora, Wagner, Gerd summery November 2002 collaborative learning communities knowledge management peer-to-peer agent-oriented architecture Guizzadi, Renata S. S. A. Koumpis Lora Aroyo Dimitri Konstantas A. Symeonidis D. Kechagias et al. summery 6-8 February 2003 keyword keyword Renata Guizzardi D. Kechagias A. Symeonidis I.Athanasiadis A. Koumpis G.Perez summery 6-8 February 2003 keyword keyword