K. Rivers, und K. Koedinger. Intelligent Tutoring Systems, Volume 8474 von Lecture Notes in Computer Science, Springer International Publishing, (2014)
C. Watson, F. Li, und J. Godwin. Proceedings of the 11th International Conference on Advances in Web-Based Learning, Seite 228--239. Berlin, Heidelberg, Springer-Verlag, (2012)
J. Moghadam, R. Choudhury, H. Yin, und A. Fox. Proceedings of the Second (2015) ACM Conference on Learning @ Scale, Seite 261--266. New York, NY, USA, ACM, (2015)