APA-viite (7. p.)

Heckman, J., Tobias, J. L., & Vytlacil, E. (2000). Simple estimators for treatment parameters in a latent variable framework with an application to estiamting the returns to schooling. National Bureau of Economic Research.

Chicago-viite (17. p.)

Heckman, James, Justin L. Tobias, ja Edward Vytlacil. Simple Estimators for Treatment Parameters in a Latent Variable Framework with an Application to Estiamting the Returns to Schooling. Cambridge: National Bureau of Economic Research, 2000.

MLA-viite (9. p.)

Heckman, James, et al. Simple Estimators for Treatment Parameters in a Latent Variable Framework with an Application to Estiamting the Returns to Schooling. National Bureau of Economic Research, 2000.