1. Associate Professor, Research Center for Knowledge Communities, Faculty of Library, Information and Media Science; University of Tsukuba; 1-2, Kasuga Tsukuba Ibaraki 3058550 JAPAN
2. Senior Lecturer, School of Computing; Dublin City University; Glanevin Dublin 9 IRELAND
3. Senior Researcher, School of Information; University of Tampere; Kalevantie 4 Tampere FINLAND
4. Senior Lecturer, Information Studies at Åbo Akademi University; Domkyrkotorget 3 20500 Åbo FINLAND
5. Assistant Professor, Faculty of Library, Information and Media Science; University of Tsukuba; 1-2, Kasuga Tsukuba Ibaraki 3058550 JAPAN