APA (7th ed.) Citation

Cook, R. C., & Lecht, J. (1968). People!: An introduction to the study of population. Columbia Books.

Chicago Style (17th ed.) Citation

Cook, Robert C., and Jane Lecht. People!: An Introduction to the Study of Population. Washington: Columbia Books, 1968.

MLA (9th ed.) Citation

Cook, Robert C., and Jane Lecht. People!: An Introduction to the Study of Population. Columbia Books, 1968.