Zaric, Nadja, Vlatko Lukarov, and Ulrik Schroder. “A Fundamental Study for Gamification Design: Exploring Learning Tendencies’ Effects”. International Journal of Serious Games 7, no. 4 (December 4, 2020): 3 - 25. Accessed May 15, 2021. https://journal.seriousgamessociety.org/~serious/index.php/IJSG/article/view/356.