Lennart E. Nacke and Sebastian Deterding edited a Special Issue of “Computers in Human Behavior” (in press) dedicated to the establishment of gamification research as cross-disciplinary field. The issue includes an analysis of this development with an outlook on the future of gamification research and ten significant articles on gamification of the past two years.
http://www.sciencedirect.com/science/article/pii/S0747563216308111