Cita APA (7a ed.)

Altonji, J. G., Elder, T. E., & Taber, C. (2000). Selection on observed and unobserved variables: Assessing the effectiveness of Catholic schools. National Bureau of Economic Research.

Cita Chicago Style (17a ed.)

Altonji, Joseph G., Todd E. Elder, y Christopher Taber. Selection on Observed and Unobserved Variables: Assessing the Effectiveness of Catholic Schools. Cambridge, MA: National Bureau of Economic Research, 2000.

Cita MLA (9a ed.)

Altonji, Joseph G., et al. Selection on Observed and Unobserved Variables: Assessing the Effectiveness of Catholic Schools. National Bureau of Economic Research, 2000.