APA (7th ed.) Citation

Clarke, J. I. (1972). Population geography (2nd ed.). Pergamon Press.

Chicago Style (17th ed.) Citation

Clarke, John I. Population Geography. 2nd ed. Oxford ; New York: Pergamon Press, 1972.

MLA (8th ed.) Citation

Clarke, John I. Population Geography. 2nd ed. Pergamon Press, 1972.