Combs, Julie P., David Clark, George W. Moore, Anthony J. Onwuegbuzie, Stacey L. Edmonson, and John R. Slate. 2011. “Academic Achievement for Fifth-Grade Students in Elementary and Intermediate School Settings: Grade Span Configurations”. Current Issues in Education 14 (1). https://cie.asu.edu/ojs/index.php/cieatasu/article/view/677.