Andrew Ravenscroft, Stefanie N. Lindstaedt, Carlos Delgado Kloos, Davinia Hernández Leo: 21st Century Learning for 21st Century Skills - 7th European Conference of Technology Enhanced Learning, EC-TEL 2012, Saarbrücken, Germany, September 18-21, 2012. Proceedings. Lecture Notes in Computer Science 7563, Springer 2012, ISBN 978-3-642-33262-3