Anne Lejeune Muriel Ney Armin Weinberger Margus Pedaste Lars Bollen Tasos Hovardas Ulrich Hoppe Ton de Jong A Graphical Modeling Language for Computer-Based Learning Scenarios. 734-735 2009 ICALT http://dx.doi.org/10.1109/ICALT.2009.103 conf/icalt/2009 db/conf/icalt/icalt2009.html#LejeuneNWPBHHJ09a