Antje Proske Hermann Körndle Susanne Narciss The Exercise Format-Editor - Supporting the Systematic Construction of Interactive Learning Tasks. 429-435 2005 conf/lit/2005 Leipziger Informatik-Tage db/conf/lit/lit2005.html#ProskeKN05 http://subs.emis.de/LNI/Proceedings/Proceedings72/article3831.html