APA (7th ed.) Citation

Clotfelter, C. T., Ladd, H. F., & Vigdor, J. L. (2007). Are teacher absences worth worrying about in the US? National Bureau of Economic Research.

Chicago Style (17th ed.) Citation

Clotfelter, Charles T., Helen F. Ladd, and Jacob L. Vigdor. Are Teacher Absences Worth Worrying About in the US? Cambridge, Mass: National Bureau of Economic Research, 2007.

MLA (9th ed.) Citation

Clotfelter, Charles T., et al. Are Teacher Absences Worth Worrying About in the US? National Bureau of Economic Research, 2007.

Warning: These citations may not always be 100% accurate.