Cita APA (7a ed.)

Giorgi, E. E. S., Baume, G. L., Vázquez, R. Á., & Feinstein, A. (2001). CCD UBVI photometry and polarimetry in the open cluster Trumpler 21.

Cita Chicago Style (17a ed.)

Giorgi, Edgard Ervar Salvador, Gustavo Luis Baume, Rubén Ángel Vázquez, y Alejandro Feinstein. CCD UBVI Photometry and Polarimetry in the Open Cluster Trumpler 21. 2001.

Cita MLA (8a ed.)

Giorgi, Edgard Ervar Salvador, et al. CCD UBVI Photometry and Polarimetry in the Open Cluster Trumpler 21. 2001.