Cita APA (7a ed.)

Birley, A. R. (1999). Septimius Severus: The African emperor. Routledge.

Cita Chicago Style (17a ed.)

Birley, Anthony Richard. Septimius Severus: The African Emperor. London [etc.]: Routledge, 1999.

Cita MLA (9a ed.)

Birley, Anthony Richard. Septimius Severus: The African Emperor. Routledge, 1999.