@misc{Koniewski_Maciej_Estimating,
 author={Koniewski, Maciej},
 howpublished={online},
 publisher={Educational Research Institute},
 type={article},
 title={Estimating the effect of class size on academicachievement by ex post facto experiment},
 keywords={sociology of education, quasi-experimentalresearch, academic achievement measurement, class size effect},
}