„High ethnic diversity of schools hampers to a similar degree the educational performance of students with an immigrant background in all destination countries, regardless of the level of stratification of their educational systems.“
Univ.-Prof. Dr. Jaap Dronkers u.a., „Positive but also Negative Effects of Ethnic Diversity in Schools on Educational Performance?“ in Windzio (Hrsg.), „Integration and Inequality in Educational Intitutions“ (2013), S. 92