Cita APA (7th ed.)

Freeman, H. (1962). Finite differences for acturial students (2nd.). Univ. Press.

Cita Chicago (17th ed.)

Freeman, Harry. Finite Differences for Acturial Students. 2nd. Cambridge: Univ. Press, 1962.

Cita MLA (9th ed.)

Freeman, Harry. Finite Differences for Acturial Students. 2nd. Univ. Press, 1962.