Andreas Vilela Marcio Cardoso Daniel Martins Arnaldo Santos Lucia Moreira Hugo Paredes Paulo Martins Leonel Morgado Privacy Challenges and Methods for Virtual Classrooms in Second Life Grid and OpenSimulator. 167-174 2010 VS-GAMES http://doi.ieeecomputersociety.org/10.1109/VS-GAMES.2010.30 conf/vsgames/2010 db/conf/vsgames/vsgames2010.html#VilelaCMSMPMM10