1. Allport, G.W., 1954. The nature of prejudic. Addison-Wesley, Cambridge, MA.
2. Paolini, S., Hewstone, M., Cairns, E., Voci, A., 2004. Effects of direct and indirect cross-group friendships on judgments of Catholics and Protestants in Northern Ireland: The mediating role of an anxiety-reduction mechanism. Personality and Social Psychology Bulletin 30, 770-786.
3. Pettigrew, T.F., Tropp, L.R., 2006. A meta-analytic test of intergroup contact theory. Journal of Personality and Social Psychology, 90, 751-783.
4. Pettigrew, T.F., Tropp, L.R., 2008. How does intergroup contact reduce prejudice? Meta-analytic tests of three mediators. European Journal of Social Psychology 38, 922-934.
5. Putnam, R.D., 2007. E Pluribus Unum: Diversity and community in the Twenty-first century. The 2006 Johan Skytte Prize Lecture. Scandinavian Political Studies 30, 137-174.