Cita APA (7th ed.)

Keyfitz, N., & Beekman, J. A. (1984). Demography through problems. Springer-Verlag.

Cita Chicago (17th ed.)

Keyfitz, Nathan, i John A. Beekman. Demography Through Problems. New York: Springer-Verlag, 1984.

Cita MLA (9th ed.)

Keyfitz, Nathan, i John A. Beekman. Demography Through Problems. Springer-Verlag, 1984.