Martin Rehák Lukás Foltýn Michal Pechoucek Petr Benda Trust Model for Open Ubiquitous Agent Systems. 536-542 2005 conf/iat/2005 IAT http://doi.ieeecomputersociety.org/10.1109/IAT.2005.136 db/conf/iat/iat2005.html#RehakFPB05