1. Dicheva, D., Dichev, C.: Gamification in education: where are we in 2015? In: E-Learn 2015, Kona, Hawaii, US, pp. 1445–1454 (2015)
2. Dicheva, D., Dichev, C., Agre, G., Angelova, G.: Gamification in education: a systematic mapping study. Educ. Technol. Soc. 18, 75–88 (2015)
3. The Right to Education | Education | United Nations Educational, Scientific and Cultural Organization. http://www.unesco.org/new/en/right2education
4. Antonaci, A., Klemke, R., Stracke, C.M., Specht, M.: Gamification in MOOCs to enhance users’ goal achievement. In: Proceedings of IEEE Global Engineering Education Conference (EDUCON 2017), 25–28 April, Athens Greece. IEEE Xplore (2017)
5. Chang, J.W., Wei, H.Y.: Exploring engaging gamification mechanics in massive online open courses. Educ. Technol. Soc. 19, 177–203 (2016)