G. Attwell, J. Cook, and A. Ravenscroft. 2nd World Summit on the Knowledge Society (WSKS 2009), Crete, Greece, (2009), 49, page 15-25. Springer, (2009)
R. Maier, and A. Schmidt. 4th Conference Professional Knowledge Management - Experiences and Visions (WM '07), Potsdam, 1, page 325-334. Berlin, GITO, (2007)