Abdolhossein Sarrafzadeh, Hamid Gholam Hosseini, Chao Fan, Scott P. Overmyer. Facial Expression Analysis for Estimating Learner?s Emotional State in Intelligent Tutoring Systems. In 2003 IEEE International Conference on Advanced Learning Technologies (ICALT 2003), 9-11 July 2003, Athens, Greece. pages 336-337, IEEE Computer Society, 2003. [doi]