Russell, G. W., di Lullo, S. L., & di Lullo D. (1988-89). Effects of observing competitive and violent versions of a sport. Current Psychology: Research and Reviews, 7 (4), 312-321.

Abstract:  66 British male college students viewed either a film clip featuring hockey fights, a film of nonaggressive hockey action, or no film after having first been angered or treated politely by an experimental confederate. The dependent variable was represented by the Mood Adjective Check List and a behavioral measure of retaliatory aggression. Analyses revealed that both angered and nonangered Ss exhibited an increase in aggressive mood following exposure to the fight film. However, while angered Ss were more aggressive than nonangered, only angered Ss retaliated against the confederate after viewing the fight film. (PsycINFO Database Record (c) 2004 APA, all rights reserved)