Schiller, E.-M., D. Strohmeier, and C. Spiel. “Are Video and Computer Games a Risk? Playing Video-and Computer Games and Aggression in 12-and 16- Year Old Adolescents”. Swiss Journal of Educational Research, vol. 31, no. 1, June 2009, pp. 75-98, doi:10.24452/sjer.36.1.4809.