Toftedahl, Marcus, Per Backlund, and Henrik Engström. “Missing: Understanding the Reception of a Serious Game by Analyzing App Store Data”. International Journal of Serious Games 5, no. 4 (December 18, 2018): 3-22. Accessed March 25, 2019. http://journal.seriousgamessociety.org/index.php/IJSG/article/view/251.