Artificial Intelligence in Education 17th International Conference, AIED 2015, Madrid, Spain, June 22-26, 2015. Proceedings / / edited by Cristina Conati, Neil Heffernan, Antonija Mitrovic, M. Felisa Verdejo. // Springer eBooks. URL: http://dx.doi.org/10.1007/978-3-319-19773-9