Model Building as a Platform to Support Thinking in Problem Solving. - Chwee Beng Lee; Ioan Gelu Ionas; Matthew Schmidt (ICCE, 2005)

The evolution of a collaborative authoring system for non-linear hypertext: A design-based research study. - Johannes Strobel; David H. Jonassen; Ioan Gelu Ionas (Comput. Educ., 2008)