1. Bickmore, T., 2003. Relational Agents: Effecting Change through Human–Computer Relationships. Ph.D. thesis, MIT Media Arts and Science.
2. Breazeal, C., 2003. http://robotic.media.mit.edu/projects/Leonardo/Leo-robot.html
3. Descartes’ Error;Damasio,1994
4. Positive Affect and Decision Making;Isen,2000
5. The Nature of the Child;Kagan,1984