1. World Robotics (2004) Statistics, market analysis, forecasts, case studies and profitability of robot investment. Sales No. GV.E.04.0.20 or ISBN No. 92-1-101084-5
2. Reeves B, Nass C (1996) The media equation: how people treat computers, televisions and new media like real people and places. Cambridge University Press, New York
3. Cowie R, Douglas-Cowie E, Tsapatsoulis N, Votsis G, Kollias S, Fellenz W, Taylor JG (2001) Emotion recognition in human–computer interaction. IEEE Signal Process Mag 18(2):32–80
4. Picard R (1997) Affective computing. The MIT Press, Cambridge
5. Walter WG (1963) The living brain. W. W. Norton, New York