N. Anderson, und C. Lin. ITiCSE '09: Proceedings of the 14th annual ACM SIGCSE conference on Innovation and technology in computer science education, Seite 243--247. New York, NY, USA, ACM, (2009)
Y. Lin, Y. Chi, S. Zhu, H. Sundaram, und B. Tseng. WWW '08: Proceeding of the 17th international conference on World Wide Web, Seite 685--694. New York, NY, USA, ACM, (2008)