RonPub UG (haftungsbeschränkt) http://www.ronpub.com Ian Pösse Sven Groppe Multi-Game Code-Duel for Learning Programming Languages 1-23 2019 Open Journal of Information Systems (OJIS) 6 6 http://nbn-resolving.de/urn:nbn:de:101:1-2020011918334950197619 https://www.ronpub.com/ojis/OJIS_2019v6i1n01_Groppe.html https://www.ronpub.com/OJIS_2019v6i1n01_Groppe.pdf