Παραπομπή σε μορφή APA (7η εκδ.)

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

Παραπομπή σε μορφή Chicago (17η εκδ.)

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

Παραπομπή σε μορφή MLA (9th εκδ.)

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