Cita APA (7th ed.)

Keyfitz, N., & Flieger, W. (1968). World population: An analysis of vital data. University of Chicago Press.

Cita Chicago (17th ed.)

Keyfitz, Nathan, i Wilhelm Flieger. World Population: An Analysis of Vital Data. Chicago: University of Chicago Press, 1968.

Cita MLA (9th ed.)

Keyfitz, Nathan, i Wilhelm Flieger. World Population: An Analysis of Vital Data. University of Chicago Press, 1968.