1. An ethological and emotional basis for human–robot interaction
2. Breazeal, C. (2000). Sociable machines: Expressive social exchange between humans and robots. Unpublished doctoral dissertation, Department of Electrical Engineering and Computer Science, MIT Press, Cambridge, MA.
3. Toward sociable robots
4. Casper, J. (2002). Human-robot interactions during the robot-assisted Urban Search and Rescue response at the World Trade Center. Unpublished master's thesis, Computer Science and Engineering, University of South Florida, Tampa, FL.