APA-referens (7:e uppl.)

Borlaza, C., Mejia, J., & Sarabia, A. (1991). A Systems study of R.A. hats. College of Engineering.

Chicago-referens (17:e uppl.)

Borlaza, Carlo, Jonstein Mejia, och Allan Sarabia. A Systems Study of R.A. Hats. Diliman, Quezon City: College of Engineering, 1991.

MLA-referens (9:e uppl.)

Borlaza, Carlo, et al. A Systems Study of R.A. Hats. College of Engineering, 1991.