APA (7th ed.) Citation

Clotfelter, C. T., Ladd, H. F., & Vigdor, J. L. (2006). The academic achievement gap in grades 3 to 8. National Bureau of Economic Research.

Chicago Style (17th ed.) Citation

Clotfelter, Charles T., Helen F. Ladd, and Jacob L. Vigdor. The Academic Achievement Gap in Grades 3 to 8. Cambridge, Mass: National Bureau of Economic Research, 2006.

MLA (9th ed.) Citation

Clotfelter, Charles T., et al. The Academic Achievement Gap in Grades 3 to 8. National Bureau of Economic Research, 2006.