The impact of individual, competitive, and collaborative mathematics game play on learning, performance, and motivation
Journal of Educational Psychology (2013) - Comment
doi: 10.1037/a0032688  issn: 1939-2176  issn: 0022-0663 

Jan L. Plass, Paul A. O'Keefe, Bruce D. Homer, Jennifer Case, Elizabeth O. Hayward, Murphy Stein, Ken Perlin